Under his so-called “sunset” clause, the tiers would be lifted on February 3, with MPs offered a vote to extend them.
The gesture marks a ramping up in the PM’s efforts to head off a backbench rebellion in the Commons this week amid widespread fury of the allocation of the new tiers.
This means he may struggle to push the measures through Parliament when they come to a vote on Tuesday.
But, in a bid to avert such challenges, the Prime Minister’s letter to Tory MPs stresses that the Government will review local areas’ tiers every fortnight.
“Regulations have a sunset of 3 February,” he wrote.
“After the fourth fortnightly review (27 January), parliament will have another vote on the tiered approach, determining whether the measures stay in place until the end of March.”
Mr Johnson also said the first such review, on December 16, would consider the views of local directors of public health, with a final decision on whether any areas should change tiers made at a Cabinet committee. The changes would come into effect on December 19.
In a further olive branch to MPs, the Prime Minister committed to publish more data and outline what circumstances need to change for an area to move down a tier, as well analysis of the health, economic and social impacts of the measures taken to suppress coronavirus.
Only the Isle of Wight, Cornwall, and the Isles of Scilly will be under the lightest Tier 1 controls, while large swathes of the Midlands, North East and North West are in the most restrictive Tier 3.
In total, 55 million people will enter Tier 2 or 3, which will see tough restrictions placed on bars and restaurants and a ban on households mixing indoors.
Several senior Tories have expressed opposition to the plan, including the 1922 Committee chairman Sir Graham Brady who said he wanted to see people “treated as adults” and trusted with their own health decisions.
He told BBC Radio 4’s Any Questions on Saturday: “I find so many people have been engaged in a wholly responsible way in trying to make sure they can continue some kind of family life, some kind of social life, but being safe, being responsible throughout.
“Especially the older people, who are typically more vulnerable to Covid-19, are also the people who are likely to be most responsible.”
Tory MP Craig Mackinlay, who represents South Thanet which has the second highest R-rate in the UK, said he is planning to vote against the new tiered restrictions on Tuesday.
He told BBC Breakfast that he would instead favour natural “self-regulation” which he says happens when people see the R-rate in their local area starting to rise.
But Chris Hopson, chief executive of NHS Providers, urged MPs to think what the NHS might be like in January, saying: “You need to take the precautions now to ensure that the NHS doesn’t get overwhelmed at what is always its busiest time of year.”
Mr Johnson acknowledged on Friday that people felt “frustrated”, particularly in areas with low infection rates which now face tighter restrictions than before the lockdown.
He said: “The difficulty is that if you did it any other way, first of all you’d divide the country up into loads and loads of very complicated sub-divisions – there has got to be some simplicity and clarity in the way we do this.
“The second problem is that, alas, our experience is that, when a high incidence area is quite close to a low incidence area, unless you beat the problem in the high incidence area, the low incidence area, I’m afraid, starts to catch up.”
– Mr Johnson appointed Nadhim Zahawi as a health minister responsible for the deployment of coronavirus vaccines.
Meanwhile, Conservative former health secretary Lord (Andrew) Lansley said the Government was “wrong” to relax coronavirus restrictions over Christmas, though admitted saying so made him “feel like the Grinch”.
Asked in an interview with Times Radio whether ministers had made an error by allowing families to gather for five days over the festive period, he said: “I think the short answer is yes – I think it was wrong…
“We’ve got to protect old people. And it really is difficult, I think, to suddenly say Christmas, well, let’s not do that. Let’s allow people to mix. Why would we do that?
“We are potentially only maybe weeks, well, perhaps months, but not many months away from the point at which we may be able to vaccinate the most vulnerable and our oldest population?
“Why expose them to any risk in that period? Why allow transmission potentially to accelerate even for a short period?”