ITV News Political Correspondent Romilly Weeks reports on Dominic Cummings' lengthy testimony to MPs
In lengthy testimony to MPs, he said his relationship with Mr Johnson had soured because "the prime minister knew I blamed him for the whole situation and I did".
He said that by the end of October their relationship had "essentially already finished" after disagreements over the handling of the coronavirus crisis.
“The heart of the problem was fundamentally I regarded him as unfit for the job and I was trying to create a structure around him to try and stop what I thought were extremely bad decisions and push other things through against his wishes," Mr Cummings told the combined Health and Technology committees.
“He had the view that he was Prime Minister and I should just be doing what he wanted me to.”
Mr Cummings also called for an immediate inquiry into the pandemic, saying "tens of thousands of people died who didn't need to die" from coronavirus.
He told MPs a lot of the problems causing the death of so many were "still in place now".
He added: "And the longer it's delayed, the more people will rewrite memories, the more documents will go astray, the more the whole thing will just become cancerous."
Watch in full: Dominic Cummings' evidence on UK government's handling of Covid crisis
Hancock remained in the job because "he's the person you fire when an inquiry comes along."
Mr Cummings said Health Secretary Matt Hancock should "have been fired for at least 15-20 things", including "lying".
He accused the Health Secretary of "criminal, disgraceful behaviour that caused serious harm" over his target to reach 100,000 tests a day by the end of April.
He added he had asked the prime minister to sack Mr Hancock "almost every week, some times almost every day" but that the Mr Johnson was told to keep him "because he's the person you fire when an inquiry comes along".
Mr Cummings also said claims the government had put a protective shield around care homes during the pandemic are "complete nonsense".
He blamed Mr Hancock for the failure to test residents returning to care homes from hospital saying: "Hancock told us that people were going to be tested before they went back to care homes, what the hell happened?"
"Quite the opposite of putting a shield round them, we sent people with Covid back to the care homes."
Chairman of the health select committee Jeremy Hunt said they were "very serious allegations said under parliamentary privilege" and urged Mr Cummings to provide evidence of his claims before Mr Hancock appeared in front of MPs in a fortnight.
A spokesman for the Secretary of State for Health and Social Care said: “At all times throughout this pandemic the Secretary of State for Health and Social Care and everyone in DHSC has worked incredibly hard in unprecedented circumstances to protect the NHS and save lives.
“We absolutely reject Mr. Cummings' claims about the Health Secretary.
“The Health Secretary will continue to work closely with the Prime Minister to deliver the vaccine rollout, tackle the risks posed by variants and support the NHS and social care sector to recover from this pandemic.”
During the evidence, Mr Cummings said:
The prime minister viewed Covid as "a scare story" and "a new swine flu"
The government had "fallen disastrously short" of public expectations
Mr Johnson was more worried about the economy at the beginning of the pandemic than the coronavirus itself
Said he was "extremely sorry" about the episode over his controversial trip to Durham during the first wave and said there were security issue he had not previously revealed
He had not been attending COBRA meetings, saying information was leaked
On the day Mr Cummings warned the PM about the need to increase mitigation measures, the government was distracted by a plea from Donald Trump to bomb the Middle East and a newspaper story about Boris Johnson's dog
Claimed the then Cabinet Secretary said, in a meeting, the prime minister should encourage people to have "chicken pox parties" to spread the disease and get herd immunity
He compared the government's reaction to a Spider-Man meme with everyone pointing responsibility at each other
He attacked the Health Secretary saying he should "have been fired for at least 15-20 things" and said Hancock was almost sacked in April
Any system that gave the public a choice between Jeremy Corbyn and Boris Johnson had gone "extremely badly wrong"
He characterised the Covid response as "lions led by donkeys"
Cummings claimed "If I had acted earlier then lots of people might still be alive"
Cummings said he was wrong not to resign in September and said he considered resigning in March if the situation was still not under control saying to colleagues he would tell the PM "I will resign and hold a press conference and say that the government is going to kill 100s of thousands of people"
Panic as the pandemic took off - "a new swine flu"
In wide-ranging testimony before the combined Health and Science committees, Mr Cummings claimed Boris Johnson thought Covid was a "scare story" and "a new swine flu" in February, adding the prime minister joked: "I'm going to get Chris Whitty to inject me with it live on television, everyone realises there's nothing to be frightened of."
Mr Johnson defended his record at Prime Minister's Questions today saying the "handling of this pandemic has been one of the most difficult things this country has had to do for a very long time and none of the decisions have been easy".
ITV News Political Editor Robert Peston reacts to the allegations made by Dominic Cummings about the government's handling of the virus
Want to hear from Robert? Listen to our political podcast, Calling Peston:
Asked if he had been complacent about the virus, Mr Johnson said: "I don't think anybody could credibly accuse this Government of being complacent about the threat that this virus posed at any point."
Mr Cummings claimed he warned the prime minister on March 12 to "announce today, not next week, if you feel ill with cold or flu stay home".
He claimed he said, in a message to Mr Johnson, "we're looking at 100,000 to 500,000 deaths between optimistic and pessimistic scenarios".
"The Prime Minister's girlfriend was going completely crackers about this story and demanding that the press office deal with that," Cummings said.
"So we had this sort of completely insane situation in which part of the building was saying are we going to bomb Iraq?
"Part of the building was arguing about whether or not we're going to do quarantine or not do quarantine, the Prime Minister has his girlfriend going crackers about something completely trivial."
Analysis from ITV News Political reporter Shehab Khan: What do MPs think?
The comments were undoubtedly shocking but what did the MPs who actually asked the questions make of it all?
One, who asked several questions, said they were initially sceptical but told me they felt what Mr Cummings’ account was “entirely believable but of course you have to question his motives".
Another, who seemed rather exasperated at the end of the seven-hour marathon session, told me that Mr Cummings was more forthright than they thought but did note that “there were some points that I sensed he held back on”.
"I should say, he gave us more time than any Minister has, including Matt Hancock."
Coincidentally the Health Secretary will be appearing in front of the same committee in a couple of weeks - lets see if he sticks around for seven hours!
The Tory backbenchers who I spoke to who watched today's events didn't seem overly concerned. One, who has been rather critical of the Prime Minister in the last year, told me they didn’t think Mr Cummings’ evidence was particularly damaging.
“He went along with all of this. If it bothered him he should have resigned but now that he has fallen out with the Prime Minister he has a lot to say,” the MP told me.
Another says that their constituents are not remotely interested in what they described as “Westminster chit-chat”.
“This doesn’t affect them in the slightest.”
For those like myself who are plugged into the ongoings of Westminster today’s viewing was blockbuster stuff – but, forgive the cliché, will any of this actually cut-through?
Conservative MPs don’t seem to think so but as talk of the COVID inquiry becomes more frequent this could ultimately be just one part of a bigger issue.
Mr Cummings claimed then Cabinet Secretary Mark Sedwill advised the prime minister to encourage the public to have "chicken pox parties" to spread the disease.
He apologised to the families who had lost relatives saying the government had fallen "disastrously short" of standards, adding "when the public needed us most, the government failed".
Mr Cummings has been vocal in his condemnation of Boris Johnson, Health Secretary Matt Hancock, and others since leaving government after a behind-the-scenes power struggle in November.
Speaking to MPs, he said he was "baffled" at denials from Number 10 that herd immunity was a plan in government.
He alleged senior officials "were all briefing senior journalists" that that was the plan.
He said he considered resigning in March if the situation was still not under control, saying he would tell the PM: "I will resign and hold a press conference and say that the government is going to kill 100s of thousands of people."
He said the prime minister was more worried about the economy at the beginning of the pandemic than coronavirus itself, and added it was wrong to suggest that Rishi Sunak had been against locking down.
"Fundamentally the prime minister just never... didn't really think that this was the big danger," he said
He added: "There have been lots of reports and accusations that the Chancellor was the person who was kind of trying to delay in March. That is completely, completely wrong."
The trip to Barnard Castle - "I wish I'd never heard of Barnard Castle"
One of the major issues discussed at the hearing was Mr Cummings' trip to Durham during the pandemic.
Mr Cummings told MPs he was "extremely sorry" about the episode and "that whole episode was definitely a major disaster for the Government and for the Covid policy", but said there were security issues he had not previously revealed.
He said in February his wife had told him there was a gang outside the family home "saying they're going to break into the house and kill everybody inside", and it was decided with the Cabinet Office after that - combined with press coverage with prompted more threats - that he would move his family out of London to his parents' home in County Durham regardless of lockdown rules.
After his trip was reported by newspapers, he said: "The Prime Minister and I agreed that because of the security things, we would basically just stonewall the story and not say anything about it.
"I was extremely mindful of the problem that when you talk about these things, you cause more trouble for yourself, and I'd already put my wife and child in the firing line on it. So I said, I'm not talking about this, we should shut our mouths about it."
He added: "I wish I'd never heard of Barnard Castle, I wish I'd never gone."
Test, trace and the border - "I should've been the mayor from Jaws"
The government should have paid people to stay at home and isolate if they had Covid symptoms, Mr Cummings said.
Pointing to the South Korean system, Mr Cummings told MPs it was "a combination of stick and carrot".
"It's much stricter in terms of legal things, like you'll get put in jail if you break the quarantine," he said.
"But we also will provide food to your door, we will pay you so you're not financially disadvantaged etc, like lots of things essentially, if we just cut and pasted what they were doing in Singapore or Taiwan or whatever and just said 'that's our policy', everything would have been better. I think it's just no doubt about that at all."
Amid recent criticism about the border policies, Mr Cummings said the prime minister never wanted a serious border policy to combat coronavirus as he sought to prioritise the travel industry.
He added "at that point he was back to 'lockdown was all a terrible mistake, I should've been the mayor of Jaws, we should never have done lockdown one, the travel industry will all be destroyed if we bring in a serious border policy'.
"To which, of course, some of us said there's not going to be a tourism industry in the autumn if we have a second wave, the whole logic was completely wrong."
The second lockdown - PM decided to "hit and hope"
The testimony was broken into four sections with the final part focusing on the handling of the virus in September and discussions over a circuit-breaker lockdown.
Dominic Cummings said Boris Johnson was not persuaded there needed to be a circuit-breaker lockdown in September and decided to just "hit and hope".
Mr Cummings said he had heard his former boss say the now infamous line that he would rather see "bodies pile high in their thousands" than order a third lockdown.
He said the comments were made after Mr Johnson had agreed to take England into a second lockdown.
He said Johnson was angry with advisors about the second lockdown and said it was a "great misunderstanding...that because it nearly killed him therefore he must've taken it seriously.
"But in fact after the first lockdown his view was... he was cross with me and for others with what he regarded as basically pushing him into the first lockdown.
"He also essentially thought that he'd been gamed on the numbers in the first lockdown and thought the NHS would somehow have got through..
Johnson as PM - "crackers that Boris Johnson was in there"
Dominic Cummings said he regarded Boris Johnson as "unfit for the job" of Prime Minister.
He said the fact the public had to choose between Mr Johnson and Jeremy Corbyn in the 2019 election meant it was clear the electoral system had "gone extremely, extremely badly wrong".
He also said that "in any sensible, rational government" he would have not had the power he did.
"It is completely crazy that I should have been in such a senior position in my personal opinion," he said.
"I'm not smart. I've not built great things in the world.
"It's just completely crackers that someone like me should have been in there, just the same as it's crackers that Boris Johnson was in there, and that the choice at the last election was Jeremy Corbyn."
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