They will join tens of thousands of nurses walking out on 6 February, after the Royal College of Nursing earlier announced further industrial action on this date.
It will be the first time nurses and ambulance staff strike on the same day, as NHS leaders fear staff and patients will be impacted by the “prolonged war of attrition” between the government and unions.
Rachel Harrison, GMB national secretary, said in a statement: “GMB’s ambulance workers are angry. In their own words ‘they are done’.
"Our message to the government is clear - talk pay now. Ministers have made things worse by demonising the ambulance workers who provided life and limb cover on strike days - playing political games with their scaremongering.
“The only way to solve this dispute is a proper pay offer. But it seems the cold, dead hands of the Number 10 and 11 Downing Street are stopping this from happening.
“In the face of government inaction, we are left with no choice but industrial action. GMB ambulance workers are determined, they’re not going to back down.”
On Monday, the NHS faces combined strikes from ambulance workers who are members of the GMB and Unison workers. Unite also said it was set to announce further ambulance worker strikes and “broaden” action across its 100,000 members.
In February, GMB members from the following NHS trusts will strike: South West Ambulance Service, South East Coast Ambulance Service, North West Ambulance Service, South Central Ambulance Service, North East Ambulance Service, East Midlands Ambulance Service, Welsh Ambulance Service, and Yorkshire Ambulance Service.
On Wednesday, as nurses began their third strike, The Independent revealed a warning from health secretary Steve Barclay, that care would have to be cut if the government met pay demands.
Mr Barclay said he wanted to “continue the constructive dialogue with union leaders” to improve working conditions and identify “areas where the NHS can become more efficient”.
The government is also facing a threat of strikes from junior doctors after the British Medical Association opened a ballot earlier this month. The results of this will be announced in early March.
Responding to more planned strikes over pay by ambulance services staff, NHS Providers’ interim chief executive Saffron Cordery said: “Four more days of strikes by GMB ambulance staff will deal another blow to already overloaded health services. And now Unite is set to announce more ambulance strikes by its members.
“We understand the strength of feeling among NHS staff and nobody wants these strikes to happen. To stave off another wave of strikes and help the NHS the government must sit down with the unions urgently and address pay for the current financial year.
“Trusts plan and prepare for industrial action to support staff and do all they can to minimise the impact on patients and day-to-day business. But with incredibly high levels of A&E attendances and delays discharging patients from hospital beds, severely hampering overstretched ambulance services, things are likely only to get worse if these strikes go ahead.”
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