Boris Johnson has been accused of “putting his head in the sand” over the threat posed by the coronavirus outbreak to a Brexit deal, after saying he has no intention of extending talks with the EU.

The prime minister is coming under growing pressure to ditch his self-imposed deadline of 31 December to reach a trade agreement with the remaining 27 states or take Britain to a no-deal Brexit on disadvantageous World Trade Organisation terms.

Many in Brussels are expecting a climbdown after the second round of talks, due to take place in London this week, were cancelled due to the health emergency on both sides of the Channel.

The EU has made clear it would accept a request for an extension to the 11-month negotiation process, which was regarded as extremely tight even before Covid-19 hit Europe.

But asked at a Downing Street press conference whether he would seek an extension beyond the end of 2020, Mr Johnson replied: “It’s not a subject that’s being regularly discussed, I can tell you, in Downing Street at the moment.

“And we’re getting on with it. There’s legislation in place that I have no intention of changing.”

The precise time of 11pm on New Year’s Eve this year is enshrined in law in the European Union (Withdrawal Agreement) Act passed by parliament earlier this year.

But acting Liberal Democrat leader Ed Davey said the PM was wrong to refuse to contemplate changing it.

“The prime minister has got his head in the sand,” said Mr Davey.

“His refusal to guarantee an extension to the Brexit talks is reckless and a dangerous example of putting politics above the needs of the country during the coronavirus crisis.

“Our NHS, jobs and the economy are already under crippling pressure due to the developing coronavirus situation and this will only increase. This is not about past debates, but focussing the country’s resources on stopping the spread of this virus.