The Prime Minister acknowledged that “lots of people think that they are in the wrong tier” but insisted the measures set to come into force on Wednesday are needed to slow the spread of Covid-19.
Sir Keir said that Labour will abstain in Tuesday’s Commons vote as it would not be in the “national interest” to vote against the measures.
“Coronavirus remains a serious threat to the public’s health and that’s why Labour accept the need for continued restrictions”, he said.
“We will always act in the national interest, so we will not vote against these restrictions in Parliament tomorrow.
“However, I remain deeply concerned that Boris Johnson’s Government has failed to use this latest lockdown to put a credible health and economic plan in place.
“We still don’t have a functioning testing system, public health messaging is confused, and businesses across the country are crying out for more effective economic support to get them through the winter months. It is short-term Government incompetence that is causing long-term damage to the British economy.
“It is imperative that the Government gets control of the virus so that our NHS can be protected and our economy recovers faster.”
Earlier on Monday, Health Secretary Matt Hancock warned Conservative MPs threatening to rebel against new coronavirus restrictions that backing them is key in avoiding a third national lockdown.
Mr Hancock said that “we’ve got this virus back under control” thanks to the lockdown but that “while we can let up a little, we can’t afford to let up a lot”.
And the Cabinet minister directly appealed to Tory backbenchers who may oppose the restrictions that will see 99 per cent of England facing major restrictions on hospitality and mixing with other households.
Asked during a Downing Street press conference if Conservatives thinking of rebelling are acting irresponsibly, he said: “I would urge all MPs right across the House to vote for the tiered system.
“The tiered system has a lower set of restrictions than the national lockdown in all three tiers.
“Unfortunately though, we do have to have the higher tier restrictions – and in particular Tier 3 restrictions – in place so that we can have confidence that we can keep getting this virus down, and then keep it under control right across the country.
“And that way, it is the best way to avoid a third lockdown. And it is the most proportionate way to take the action that we need to keep people safe, and to stop the NHS being overwhelmed.”
The latest warnings came as the Government acknowledged in its impact assessment that the new controls will have a “significant” impact on the economy but said that allowing the disease to run unchecked would be “much worse” for public health.
A failure to maintain strong controls would lead to the NHS being overwhelmed and result in an “intolerable” loss of life, the analysis published ahead of a crunch Commons vote on the restrictions on Tuesday added.