Families could be allowed to meet for up to a week over Christmas as part of a UK-wide relaxation of coronavirus rules, it has been reported.

Health Secretary Matt Hancock told a Downing Street briefing it was still too early to say what contact people will be able to have over the festive period, but it has been reported Boris Johnson is preparing to announce a plan next week for an easing of rules.

Several families could be allowed to join a bubble and to mix between December 22 and 28, the Daily Telegraph reported.

The newspaper said Mr Johnson will also warn the level of restrictions for the rest of next month would depend on how well the public obeys the current lockdown in England, which is due to end on December 2.

Downing Street declined to comment, but did not deny the report.

Addressing the coronavirus briefing on Friday, Mr Hancock said it would be a “boost” for the UK if a “safe, careful and sensible” set of plans could be agreed between the devolved nations.

He said: “Over Christmas I know how important it is that we have a system in place, a set of rules that both keeps people safe but also allows people to see their loved ones.”

Earlier this week Public Health England said Scientific Advisory Group for Emergencies (Sage) guidance had suggested each day of greater freedom could require five days of tighter measures.

But deputy chief medical officer for England Professor Jonathan Van-Tam, who also appeared at the briefing, said there is “no magic number” about how many days any easing of the rules might cost.

Meanwhile Mr Hancock said he is increasingly hopeful of some kind of normality by spring, as he confirmed the UK’s health regulator is assessing a coronavirus vaccine which could potentially be rolled out next month.

He described the consideration by the Medicines and Healthcare products Regulatory Agency (MHRA) of the Pfizer/BioNTech vaccine as “another important step forward in tackling this pandemic”.

Referring to the “ray of light” that a vaccine may bring, he confirmed he had formally asked the regulator to assess the vaccine and that, if approved, a jab could be rolled out from December.

He said: “If the regulator approves a vaccine we will be ready to start the vaccination next month with the bulk of roll-out in the new year.

“We are heading in the right direction but there is still a long way to go.”

Striking an optimistic tone, Mr Hancock said that with the news of vaccine breakthroughs in recent weeks, coupled with an expansion in mass testing, he is “more and more confident” that life will be closer to normal by spring.

It comes as NHS documents seen by the Health Service Journal (HSJ) suggest all adults in England – of any age – could start to be vaccinated against Covid-19 before the end of January if supplies allow.

Under the plan, every adult who wants a jab could be vaccinated by early April.

Prof Van-Tam, who appeared remotely as he is self-isolating due to a “household contact”, said people “shouldn’t worry too much” about where they are in the priority list because the difference between levels could be a matter of one to three weeks.

Mr Hancock told the briefing he did not want to “pre-judge” or “impinge” on the independence of the MHRA when asked how long its process could take and that the speed of a vaccine roll-out would depend on the manufacturing speed.

Mr Hancock said the second peak of the virus is “flattening” but urged the public to “keep our resolve” for the rest of the lockdown to keep cases down.

Prof Van-Tam also urged caution and suggested any gains from the second national lockdown could be quickly lost as it takes “just seconds” for the virus to spread.

He appealed to people to “keep up the pressure on this virus and push down on it as much as we can right to the end of the period (of lockdown)”.

Warning that infection rates will pick up again if the public ignores any guidelines put in place around Christmas, he said there is a “dual responsibility” for people to follow the rules set out by the Government.

Welsh First Minister Mark Drakeford earlier said he is “generally hopeful” an agreement can be reached between the UK’s four nations regarding Christmas plans.

He said issues being talked about include travel between the nations, how long any easing of restrictions might last and to what extent households may be allowed to mix, and that further talks were due to take place next week.

Northern Ireland will enter a two-week circuit-breaker next Friday and Scotland has placed two million people in its toughest level of restrictions for three weeks.

The Government said a further 511 people had died within 28 days of testing positive for Covid-19 as of Friday, bringing the UK total to 54,286, while another 20,252 lab-confirmed cases of coronavirus were reported.

On Friday, the Office for National Statistics (ONS) said there were “substantial differences” in Covid-19 infection rates across England, with rates continuing to increase in London, the east of England and the South East, but decreasing in the North West and the East Midlands.

Sage said the reproduction number – or R value – for the whole of the UK had dropped to between 1 and 1.1.