Boris Johnson is resisting mounting pressure to extend the Brexit transition period after border chaos following the discovery of a new coronavirus strain.
France, Germany, Italy, Belgium and the Netherlands imposed travel restrictions on Britain after the emergence of the new variant, which is thought to spread up to 70% more quickly.
Nicola Sturgeon said it was “imperative” to secure a delay to Britain’s departure from the EU following the latest crisis, while London Mayor Sadiq Khan said it would be “reckless” to press ahead.
However No10 flatly ruled out a delay and the prospect of “stand still” arrangements into next year.
Tory Defence Committee chairman Tobias Ellwood also urged the Government to delay, saying: “If there’s no deal by NY let’s do what’s best for the UK and pause the clock.”

Deadlocked trade talks resumed yesterday(Mon) after a Sunday deadline imposed by the European Parliament was missed.
If a trade deal is not secured by December 31, the UK will be forced to resort to tariff-heavy World Trade Organisation terms - effectively a no-deal Brexit.
The PM’s official spokesman said “time is obviously in very short supply” to get a deal done and ratified but MPs could still be recalled to Parliament over Christmas.
Asked if there could be a delay, the spokesman said: “We have been clear on this point that we will either leave the transition period on December 31 with a free-trade agreement or we will leave with Australia-style WTO terms. That remains the case.”
Keir Starmer also rejected calls for an extension, demanding that the Prime Minister agrees a trade deal with the European Union this week.
Mr Johnson told a No10 press conference that he had spoken to French President Emmanuel Macron about border chaos but they avoided discussing Brexit.
The Prime Minister said the position was “unchanged” and admitted “there are problems” remaining.
“It’s vital that everybody understands that the UK has got to be able to control its own laws completely and also that we’ve got to be able to control our own fisheries,” he said.
“It remains the case that WTO terms would be more than satisfactory for the UK. We can certainly cope with any difficulties that are thrown in our way.”
He said the UK wanted a deal but the country would “prosper mightily” after January 1 either way.
Transport Secretary Grant Shapps claimed the handling of the roads chaos in Kent shows “we are ready” for a no-deal Brexit.
Meanwhile, French European Affairs Minister Clement Beaune told reporters: “Let’s try to find this good agreement but not an agreement at any cost.”
Brexit fears rose as the UK was cut off from large parts of Europe after countries imposed bans on travel due to the new coronavirus variant.
The Scottish First Minister said: “The new Covid strain - and the various implications of it - means we face a profoundly serious situation, and it demands our 100% attention.
“It would be unconscionable to compound it with Brexit.”
Mr Khan said securing key supply chains and fighting the coronavirus pandemic needed the “full and undivided efforts of ministers”.
He added: “Risking the chaos and uncertainty of a no-deal Brexit was reckless even before the latest surge in Covid cases and the worrying news about this latest strain.”
But the Labour leader told reporters: “I don’t want an extension – I want the deal. The Prime Minister promised a deal.
“He said he had an “oven-ready deal”. He needs to get on and deliver that.
“And just delaying it further isn’t going to help with the great uncertainty there already is for businesses.”