Wes Streeting has warned resident doctors that strikes and a jump in flu cases over the Christmas period could be “the Jenga piece” that forces the NHS to collapse.

The health secretary said the NHS faced a “challenge unlike any it has seen since the pandemic” and urged resident doctors to accept the government’s offer and end their actions.

He said: “The whole NHS team is working around the clock to keep the show on the road. But it’s an incredibly precarious situation. Christmas strikes could be the Jenga piece that collapses the tower. That’s why I am appealing directly to resident doctors to accept the government’s offer.”

NHS figures published on Thursday showed flu cases at a record level for the time of year after jumping 55% in a week to an average 2,660 patients in hospital each day last week.

Writing in the Times, Streeting said the number of patients in hospital in England could triple by the peak and described the scenes in hospital as “inexcusable”.

Dr Chris Streather, a regional medical director at NHS England, said while the impact of flu admissions on hospitals was “pretty bad” but it was “nothing like the scale” of the Covid pandemic.

Asked if talk of the NHS collapsing was over the top, Streather told BBC Radio 4’s Today programme: “The NHS is coping at the moment. The flu rates are still going up.”

He added: “It’s well within the boundaries of what we can cope with. One of the things we learned during the pandemic was our preparation for coping with large outbreaks of respiratory viruses got better. We increased the number of critical care or intensive care beds during that time, so we’re better prepared. And it’s a different scale from the situation we’re facing in March 2020, you have to prepare for the worst case.”

Streather said there were 2,500 patients in hospitals in England with flu admissions, a 55% increase on the previous week and the equivalent of three large hospitals being full of flu patients.

“It’s a significant problem,” he said. “It’s nothing like the scale of the 2020 pandemic. And I think we need to use our language to make people do the right healthy behaviours but not to cause alarm at the moment.”

The health secretary said the British Medical Association (BMA) leadership calling off planned Christmas strikes would have “given the NHS certainty this week, when it is firefighting the flu epidemic”.

The BMA said it would consult members by surveying them online on whether a new deal from the government was enough to call off strikes next week.

The online poll will close on Monday, two days before the five-day strike is due to start.

The union said the new offer includes new legislation to ensure homegrown doctors in training have priority for speciality training roles, an increase in speciality training posts over the next three years, with 1,000 of these to start in 2026, and funding mandatory examination and Royal College membership fees for resident doctors.