Cleaners at the Foreign and Commonwealth Office in London who complained to foreign secretary, Philip Hammond, about their low levels of pay, are being disciplined by their employers.

The 14 cleaning staff raised the issue of the living wage in the letter and have since received documents from cleaning contractor Interserve asking them to attend an interview that could lead to their suspension from work, or redundancy. Inteserve say the letter is unrelated to the meeting.

However the letter from Interserve, says they are under investigation for “bringing the contract into disrepute”and the Hammond letter was enclosed as evidence.

Cleaners at the FCO are currently paid just over the minimum wage, at £7.05 an hour, which will rise to the government’s so-called “national living wage” of £7.20 an hour for over-25s from next April.