About 140 cleaners at the Houses of Parliament are set to strike on Wednesday of next week.
The cleaners, members of the T&G union, are campaigning for a living wage as well as sick pay, holidays and a pension.
This will be the second day of action by the cleaners, who earn just £5.20 per hour. A number of MPs and Lords have now asked for the cleaners to receive a decent wage.
But civil servant Peter Grant Peterkin, who is in charge of the contract and gets more than £100,000 a year, is refusing to meet with the union to discuss the dispute.
Jack Dromey, T&G deputy general secretary, said, “It seems inconceivable that unelected, privileged civil servants are blocking attempts by parliamentarians to get their cleaners a living wage.”