Thousands of ambulance workers in England will strike on 10 February, Unison has announced.
The union said workers across five services will walk out as the long-running dispute over pay and staffing continues.
Ambulance workers in London, Yorkshire, the South West, North East and North West will be involved in the industrial action.
Strikes will now be happening across the NHS every day next week apart from Wednesday.
Announcing the latest industrial action, Unison urged ministers to stop “pretending the strikes will simply go away” and improve ambulance workers’ pay.
“After promising everyone a quicker pay review body process, the secretary of state’s own department failed to get its evidence in on time earlier this month, the union’s head of health Sara Gorton said.
“Ministers must stop fobbing the public off with promises of a better NHS, while not lifting a finger to solve the staffing emergency staring them in the face.
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“The government must stop playing games. Rishi Sunak wants the public to believe ministers are doing all they can to resolve the dispute. They’re not.
“There are no pay talks, and the prime minister must stop trying to hoodwink the public. It’s time for some honesty. Ministers are doing precisely nothing to end the dispute.
“The government’s tactics seem to be to dig in, wait months for the pay review body report and hope the dispute goes away. It won’t. And in the meantime, staff will carry on quitting, and patients being let down.
“There can be no health service without the staff to run it. Ministers must open proper talks to end the dispute and put in place the urgent retention plan needed to boost pay and staffing across the NHS.”
