Ministers will do “what it takes” to ensure the NHS is not overwhelmed this winter, Sajid Javid has said as he warned that the number of new infections across the UK could hit a record 100,000 a day.

The health secretary said the government would not heed the call from the NHS Confederation to implement “plan B” measures such as mandatory mask-wearing “at this time”. But he underlined the fact that ministers would be, “staying vigilant, preparing for all eventualities”.

The government has come under mounting pressure to take action to contain the virus. The latest data shows 49,139 new infections recorded in the last 24 hours, and 179 deaths.

If Javid’s warning of 100,000 cases a day came to pass, that would be higher than at any stage during the pandemic.

The health secretary previously suggested cases could hit 100,000 in the summer, when infections rose sharply as restrictions were lifted – but they went on to peak above 60,000 in July before falling away. The highest recorded daily figure for reported cases was 68,053 on 8 January.

The seven-day average of deaths, at 166, is up 21% on last week. “We cannot be complacent when Covid-19 makes such a potent threat,” Javid said.

He said the government would be redoubling its efforts to administer booster jabs to the over-50s and the clinically vulnerable. The NHS has already administered 4m top-up doses but Javid urged others to come forward.

“We’ve got the jabs: we just need the arms to put them in,” he said, calling it a “national mission” to roll out the vaccine. He urged people to come forward for their booster vaccine dose, “not just to save lives, but to keep your freedoms too”. “We must all remember that this virus will be with us for the long term and that it remains a threat,” he said.

Javid also reminded the public about how they can moderate their behaviour to help avoid the spread of the virus, including meeting outdoors where possible, wearing a face covering in crowded spaces and taking regular lateral flow tests.