The British government faced renewed pressure on Tuesday after indications it had ignored scientific advice three weeks ago for tougher restrictions to cut rising coronavirus infections.

The main opposition Labour party said the government's failure to act was alarming and raised questions about the credibility of its latest plan to curb the virus' spread.

England's chief medical officer Chris Whitty said he was "not confident" the latest measures announced by Prime Minister Boris Johnson could reverse the upward trend.

Johnson had earlier unveiled a three-tiered system categorising areas of England by rates of infection, to try to simplify a complex web of local restrictions. The northwest city of Liverpool -- the only place put into the highest category -- will see a ban on household mixing and pubs closures from Wednesday for at least four weeks.

But Whitty, flanking Johnson at a Downing Street news conference on Monday evening, urged local leaders in the most-affected areas to go further.

"I am not confident, and nor is anybody confident, that the tier three proposals for the highest rates... if we did the absolute base case, and nothing more, would be enough to get on top of it," Whitty said. "There's a lot of flexibility in the tier three level for local authorities... so that they can do significantly more than the absolute base because the base will not be sufficient."

Public health officials had said swathes of northern England should also have been placed at "very high" risk. It then emerged that scientific experts had recommended stronger action as long ago as last month, including a so-called circuit-breaker lockdown to cut transmission.

The government's Scientific Advisory Group for Emergencies (SAGE) presented ministers with a shortlist of virus interventions on September 21 "for immediate introduction".  They included closing bars, restaurants, cafes, gyms and personal services like hairdressers, banning different households from mixing in homes and switching all university and college tuition online.

But Johnson adopted only one of the five recommendations -- urging people to work from home.

'Too late again'

Johnson has been heavily criticised, not least for being too slow to move to a national lockdown in its early stages.

Britain's death toll of more than 43,000 is the worst in Europe. Nearly 14,000 new cases were reported across Britain on Monday, with 50 further deaths.

Hospital admissions are now higher than when the national lockdown was introduced on March 23. Businesses, Conservative MPs and right-wing newspapers have urged Johnson to resist another national lockdown because of the effect on the economy.

Revelations that he ignored the bulk of SAGE's advice three weeks ago prompted swift criticism from the main opposition Labour Party.

Labour health spokesman Jonathan Ashworth said he was "quite alarmed" when he saw the SAGE minutes published after Monday's news conference.

He said it raised questions about the government's repeated claim to be following the science. "Quite self-evidently they have rejected significant recommendations here from the scientists," Ashworth told BBC television.

SAGE member John Edmunds, an epidemiologist, said tougher restrictions needed to be in place "as fast as possible".

"I suspect we will see very stringent measures coming in place throughout the UK at some point but it will be too late again," he told BBC radio.