The biggest round of strike of NHS employees in its history is currently under way with more strike action planned for the rest of the week.
Ambulance crews and nurses represented by multiple unions have walked out on the same day for the first time since industrial action started in December last year.
Members of the Royal College of Nursing (RCN) union in a third of the NHS trusts in England are on strike, alongside members of two ambulance unions, the GMB and Unite.
In Wales a number of unions have suspended strike action after a new pay offer was put on the table. Only Unite is striking there.
The rest of the week will see the following strike action:
The head of RCN said strikes would be cancelled if the government brings a better pay offer to the negotiating table.
Pat Cullen, general secretary, said: "We've always said where negotiations happen, we would cancel strikes to allow for our members to be consulted.
"That's what happened in Wales, that's what's been going on in Scotland."
She appealed directly to Rishi Sunak, saying: "Get to the table, negotiate with me and what offer you put on the table I will consult our members and they will make that decision."
The national secretary of the GMS union, Rachel Harrison, said: "The NHS is crumbling, people are dying and this government is dithering."
As it stands, the government has refused to reopen talks. The pay award for this year - which is worth at least £1,400 for every NHS worker below the level of doctor - is already being paid to staff and the government is now turning its attention to next year's pay award, which is due to come out in April.
The unions have pulled out of the pay process which is overseen by the independent NHS Pay Review Body.
In Wales, the Welsh government has offered an extra 3% on top of the same payment as England. The Scottish government has also offered extra.
Head of health at Unison, Sara Gorton, said: "This ramps up the pressure on the prime minister significantly. Political leaders in Scotland and now Wales are making the Westminster government look decidedly out of touch."