There is evidence to suggest the new variant of Covid -19 - that emerged in the UK in September last year - is more deadly, the Prime Minister has warned.

Although research is at an early stage, there is “some evidence” the UK variant of coronavirus is associated with “a higher degree of mortality”, Boris Johnson said.

Speaking to the nation during the Downing Street press conference on Friday night he said: “I must tell you this afternoon that we’ve been informed today that in addition to spreading more quickly it also now appears that there is some evidence that the new variant, the variant that was first identified in London and the South East, may be associated with a higher degree of mortality.”

Mr Johnson went on to say the 38,562 Covid patients in hospital is 78% higher than it was at the first peak in April last year.

“It’s more important than ever that we all remain vigilant in following the rules and that we stay at home, protect the NHS and thereby save lives,” he said.

“All current evidence continues to show that both the vaccines we’re currently using remain effective both against the old variant and this new variant.”

The number of Covid-19 patients in hospital in England stood at 33,412 as of 8am on Friday January 22, according to the latest figures from NHS England.

This is slightly below the record 34,336 patients on January 18, and up just 0.1% on a week ago.

Four regions have seen a week-on-week rise in the number of Covid-19 patients: the Midlands, which has 6,341 patients, up 8%; north-west England, which has 4,315, up 7%; north-east England/Yorkshire, which has 3,793, up 6%; and south-west England, which has 2,273, up 1%.

Boris Johnson urged people to come forward for a “life-saving vaccine” when invited to do so.

He said: “Our immunisation programme continues at an unprecedented rate.

“5.4 million people across the UK have now received their first dose of the vaccine and over the last 24 hours we can report a record 400,000 vaccinations.

“In England, one in 10 of all adults have received their first dose, including 71% of over-80s and two-thirds of elderly care home residents.”

He added: “I say to everyone, when that letter arrives please don’t hesitate to book that appointment and get this life-saving protection because this is the best and fastest way for us all to defeat this virus and get our lives back to normal.”

The figures for the other regions are: London 7,298 patients, down 7%; south-east England 5,337, down 3%; and eastern England 4,055, down 5%.