“We’re starting to see indications that hospitalizations and death rates are increasing,” Johnson’s official spokesman Max Blain told reporters Tuesday. “Clearly we are keeping a very close eye on rising case rates.”

The U.K. reported a further 223 deaths within 28 days of testing positive for Covid-19 as of Tuesday, the highest figure since March. Some 921 people were admitted to hospitals with coronavirus last Friday; that number has been creeping up since the end of September.

However, despite warning of tough times ahead, Johnson said current measures are keeping the virus “under control,” according to a readout of his cabinet meeting with ministers issued by 10 Downing Street. 

There are no plans at the moment to bring in “Plan B,” which could include compulsory face masks and advice to work from home, which Johnson warned last month might be needed if a surge in cases threatened to overwhelm the NHS.

Weekly deaths from coronavirus have topped 800 for each of the past six weeks in Britain, which is higher than in other major western European nations, according to Bloomberg’s coronavirus tracker. To date, the U.K. has recorded almost 140,000 Covid-related fatalities.

The U.K. has seen a recent surge in cases, reporting its highest daily jump since mid-July on Sunday. It is facing calls for urgent research into a mutation of the delta variant present in Britain, known as delta plus. 

Still, hospitalizations are currently at about 20% of the levels seen during the previous peak in the U.K. and deaths at about 10%, which Blain attributed to the effects of the vaccine rollout. 

Blain told reporters that the government would only consider bringing in “Plan B” if there was a significant risk of the NHS being overwhelmed. 

“We are not at that point because of the vaccination program,” he said. 

Health Secretary Sajid Javid said Tuesday that the government will shortly set out a detailed program for how it will deal with winter pressures on the NHS. 

“Usually winters are tough for the NHS, but I think this winter will be particularly tough,” Javid said in the House of Commons.

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