Ambulance workers are to stage a 24-hour strike in a long-running row over issues including cuts.
Unite said its 450 members in the Yorkshire service, including paramedics and other staff, will walk out on 2 April and ban overtime from 26 March.
The union warned that further strikes could be held.
Unite said the Yorkshire Ambulance Service NHS Trust had derecognised the union after it raised concerns about patient safety over plans to make £46 million of savings over the next five years.
Union members voted by 61% in favour of strikes and 83% for other forms of industrial action.
More top news
On the first day of the meteorological Autumn - what will the weather have in store?
Fans are being warned that counterfeit Rugby World Cup tickets are in circulation. Here is some advice on how to avoid being conned.
George Bulman was found dead between Christmas and New Year at the home he shared with his wife Carol and son Geoffrey in Newcastle.