Sir Keir Starmer told ITV's Peston that "millions of families" are going to struggle this winter as a result of the "cost of living crisis"
Sir Keir criticised the prime minister's "levelling up" speech at the Conservative Party Conference on Wednesday, during which Mr Johnson claimed the increased cost of living caused by rising inflation, taxes and energy bills will result in a fairer "low tax" system.
The Labour leader told ITV's Peston show the speech failed to get to the heart of some of the biggest issues the country is currently facing, labelling it devoid of any major policy changes.
Sir Keir said the PM is pretending as if he's "just landed from the moon" - but that the reason the UK is plunged in a "cost of living crisis" is down to the way the Conservatives have governed for the past 11 years.
He told ITV News Political Editor Robert Peston: "The cost of living crisis I think is going to unfold as we go through the winter months, it's going to hit millions of families very, very hard.
"And I think, you know, that the showman, the jokes are all very well but they're going to wear thin when people are hit in their wallet and they're going to be hit very, very hard".
The recurring theme of the PM's address to the Tory membership in Manchester was the idea of "levelling up" and "building back better".
Mr Johnson did not announce any major new policies in his key-note speech, but he did deliver a rallying cry to the party membership as he defended his tax hikes to fund health and social care reform.
When asked by Robert Peston if he agrees with Mr Johnson’s view that the UK has to move to a "high-wage, high-skilled, high-productivity economy", Sir Keir insisted the Tories should have already achieved this and said they haven't because they have no "long-term strategies" in place.
Sir Keir explains why he thinks the PM is "acting as if he just landed from the moon"
Sir Keir said: “Look, the prime minister is playing this game where he’s pretending that he’s just sort of just landed from the moon and he’s looking around and saying, ‘things look pretty awful around here, we need a bit of levelling up, things are so awful’.
“And he and the Tories have been in government for 11 years, so we’re in this state because of the way that they have governed the country. They have got a lot to answer for here.
“Of course, we want a high-wage, high-skilled, high-productivity economy, but we need a plan for that, and a plan for that isn’t fuel shortages, gaps on our supermarket shelves and pretending that this is some cunning plan to drive up wages and drive up skills.”
Speaking on the cut to the £20 Universal Credit uplift, Sir Keir claimed a more generous benefit system should not be funded by more borrowing.
He said: “We will pay, we will balance the books when it comes to day-to-day spending, we will borrow to invest, so we’re very clear about that, it will have to be paid for as day-to-day spending.”
Meanwhile, Sir Keir said Metropolitan Police Commissioner Dame Cressida Dick needed to reform the force “quickly” following the failures of vetting processes in relation to Sarah Everard’s killer, former officer Wayne Couzens.
But he added focus for the failures should not fall on Dame Cressida alone.
The Labour leader replied: “There’s a systemic problem that’s been there for 10 years and we’ve been walking round and round and round it, I was looking at it when I was Director of Public Prosecutions.
“I’ve drafted a victims’ law, we’ve said to the government we will vote with them if they bring forward provisions, they haven’t done so.
“Now is the time for the government to step up when it comes to violence against women and girls.”