Downing Street has said it wants to relax lockdown rules to “ensure that people can spend time together over Christmas”, but would not reveal what system of rules will replace the current national lockdown in England.

The four-week nationwide restrictions will legally expire on December 2.

Boris Johnson has said he wants the country to then return to a system of regional measures.

No.10 said on Tuesday the precise details of what will replace the national lockdown will not be revealed until parliament is told next next week, but signalled that enabling people to enjoy the Christmas holiday was a key objective.

“It’s our intention to bring the tougher national measure to an end on December 2 and that will happen in law, and we will then move to a regionalised approach,” the prime minister’s spokesperson said.

“We are looking at ways to ensure that people can spend time with close family over Christmas at the end of what there’s been an incredibly difficult year.

“As to what that will be, I’m afraid you will have to wait a little longer.”

A return to a tiered system of local restrictions does not necessarily mean a return to the levels in place before November 5 – MPs will be given the opportunity to vote on what happens next.

It has been reported a fourth more severe level could be added, or that an entirely new regional approach might be introduced.

On Monday Dr Susan Hopkins, from Public Health England, warned there had been “very little effect” on the infection rate from tier 1 and said there would need to be a “strengthening” of the tiers.

It raises the prospect that England could exit national lockdown into tougher regional measures than it was in before, but then see them relaxed for a short period over Christmas.

Downing Street said decisions over whether to lift any restrictions would be based on a “range of different factors”.

“The R rate is obviously an important one of those. We will also want to look at our hospitalisation numbers, the number of people who are being treated in intensive care units, the pressure which the NHS is under,” Johnson’s spokesperson said. “They will all be factors to be taken into consideration.

“Obviously we’ll wait to see further data over the course of the next week or so.

“The R rate has been coming down in some parts of the country. And what we continue to do is urge people to follow the rules.”

Downing Street did not say if there was a precise R rate level, number of hospitalisations or number of people in intensive care that the government would benchmark any change in rules against.

Paul Hunter, a professor of medicine at the University of East Anglia who advises the World Health Organisation, told BBC Radio 4′s World at One programme the tier system would work well if it was more “responsive”.

“I’m hoping that we will have some further relaxation over the Christmas period,” he said.

“Maybe only for a few days but I think providing that we have some rules still in place and we avoid too big gatherings I do hope that we can manage to have a more normal Christmas than we might otherwise have been expecting.” 

No.10 also revealed that Johnson has tested negative for coronavirus but will continue his 14-day self-isolation after coming into contact with a Tory MP who had tested positive.