Nurses and ambulance workers have been striking separately on and off since late last year but Monday’s walkout involving both, largely in England, is the biggest in the 75-year history of the NHS.

Nurses will also strike on Tuesday, while ambulance staff will walk out on Friday and physiotherapists on Thursday, making the week probably the most disruptive in NHS history, its Medical Director Stephen Powis said.

Health workers are demanding a pay rise that reflects the worst inflation in Britain in four decades, while the government says that would be unaffordable and cause more price rises, and in turn, make interest rates and mortgage payments rise.

Around 500,000 workers, many from the public sector, have been staging strikes since last summer, adding to pressure on Prime Minister Rishi Sunak to resolve the disputes and limit disruption to public services such as railways and schools.

The Royal College of Nursing (RCN) trade union wrote to Sunak over the weekend asking him to bring the nursing strike “to a swift close” by making “meaningful” pay offers.

“We’ve got one of the busiest winters we have ever had with record levels of funding going into the NHS to try and manage services,” Maria Caulfield, the minister for mental health and women’s health strategy, told Sky News on Monday.

“So every percent of a pay increase takes money away.”

The government has urged people to continue to access emergency services and attend appointments during the strikes unless they had been canceled but said patients would face disruption and delays.

NURSES LEAVING

The NHS, a source of pride for most Britons, is under extreme pressure with millions of patients on waiting lists for operations and thousands each month failing to receive prompt emergency care.

The RCN says a decade of poor pay has contributed to tens of thousands of nurses leaving the profession — 25,000 over just the last year — with the severe staffing shortages impacting patient care.

The RCN initially asked for a pay rise of 5 percent above inflation and has since said it could meet the government “half way,” but both sides have failed to reach agreement despite weeks of talks.

Meanwhile, thousands of ambulance workers represented by the GMB and Unite trade unions are set to strike on Monday in their own pay dispute. Both unions have announced several more days of industrial action.

Not all ambulance workers will strike at once and emergency calls will be attended to.

In Wales, nurses and some ambulance workers have called off strikes planned for Monday as they review pay offers from the Welsh government.

Sunak said in a TalkTV interview last week he would “love to give the nurses a massive pay rise” but said the government faced tough choices and that it was funding the NHS in other areas such as by providing medical equipment and ambulances.