Post Office workers are to stage a one-day strike in a dispute over pay.
Members of the Communication Workers Union (CWU) will walk out on May 3 after voting overwhelmingly in favour of industrial action.
The union said the strike is over a pay freeze for 2021 and the offer of a 2% increase from April this year, alongside a £250 one-off lump sum.
Union officials said the offer was “exceptionally poor”, especially as RPI inflation has reached 9%.
CWU official Andy Furey said: “Despite this union’s best attempts to avoid strike action, the Post Office has displayed no interest whatsoever in meaningful negotiations.
“As such, workers have delivered an overwhelming mandate for strike action.
“The current offer of a mere 2% pay rise over two years is nothing short of an insult to these key workers who provided exemplary services to this nation during the pandemic.
“As the cost-of-living crisis mounts, working people across the country are facing stark realities.
“This isn’t any less true of Post Office employees, who deserve far better than the degrading offer currently on the table.
“Post Office management need to understand that by undervaluing these workers, they have provoked real anger across the country.
“We urge them to get round the table with us and reach a decent, fair agreement that shows respect for Britain’s key workers who kept post offices open for society during the pandemic.”
The dispute involves counter staff, as well as those in clerical, administration and call centres.
The CWU said all so-called crown post offices will be affected by the walkout as well as smaller sub-post offices.