Video report by ITV News Political Correspondent Libby Wiener
The First Secretary of State, who is "deputising" for the prime minister while he's cared for in hospital, thanked the public for their "sacrifice" but said "we are not done yet, we must keep going.”
Leaders discussed the positive impact social distancing was having on the spread of the virus, but the outcome of the meeting was that there was not enough evidence to make a decision.
“Sage will meet next week to discuss the latest evidence and we will keep the measures we’ve put in place under review.”
Mr Raab added: “We don’t expect to be able to say more on this until the end of next week.
“The measures will have to stay in place until we’ve got the evidence that clearly shows we’ve moved beyond the peak.”
Prime Minister Boris Johnson did not attend the Cobra meeting as he is receiving treatment for coronavirus in an intensive care unit.
Mr Raab said Mr Johnson was "still in intensive care but he continues to make positive steps forward and he’s in good spirits".
It comes as a total of 7,978 patients have died in hospital after testing positive for coronavirus in the UK as of 5pm on Wednesday, Mr Raab said, up by 881 from 7,097 the day before.
He said as deaths are still rising, people need to stick with lockdown restrictions.
Mr Raab added: "As we look forward to the long bank holiday easter weekend I know some people are going to start wondering is it time to ease up on the rules.
"Thank you for your sacrifice, but also we’re not done yet, we must keep going," he said.
Mr Raab said: "It’s been almost three weeks and we’re starting to see the impact of the sacrifices we’ve all made, but the deaths are still rising and we haven’t reached the peak of the virus."
"Its still to early to lift the measures that we’ve put in place, we must stick to the plan and we must continue to be guided by the science."
Earlier Welsh First Minister Mark Drakeford and Scottish First Minister Nicola warned against any relaxation decision.
Ms Sturgeon said she didn't think there was "any possibility" of restrictions being eased, while Mr Drakeford said the decision in Wales had already been made to remain in lockdown.
Ms Sturgeon told Sky News: "I don’t think there is any possibility, any likelihood, of these lockdown measures being lifted immediately, or even imminently."
Mr Johnson's spokesperson did not contradict that warning at the daily journalists' briefing held at midday on Thursday.
“What we absolutely need to do now is keep bearing down on the rate of transmission which will mean continuing with social distancing measures to ensure we are protecting the NHS and saving lives,” the spokesperson said.
The spokesperson also gave an update on the condition of Mr Johnson, who "continues to improve" while at St Thomas' Hospital in London.
The prime minister's third overnight stay in St Thomas' Hospital's ICU was "good", and he is "in good spirits", the spokesperson said.
The PM continues to receive oxygen treatment for Covid-19, there's "no change to that", he added.
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