Public and Commercial Services union (PCS), representing the cleaners working in UK palaces, has launched a campaign to boost the royal cleaners' pay to the London Living Wage of £7.85 an hour.

London Mayor Boris Johnson has approved the living wage of £7.85 an hour, and the cleaners of House of Commons and House of Lords are being paid the same rate, but only the royal cleaners are paid £6.45 per hour.

The cleaners working at the palaces were employed by KGB Holdings and Greenzone, however the PCS union claims that Royal Households is the true agent responsible for the staff.

Royal Households is reportedly receiving about £30 million a year from the taxpayers, and yet could not provide a living wage for its cleaners.

PCS general secretary Mark Serwotka said: "As the royals prepare to spend millions of pounds on Prince William's wedding, they're refusing to insist that the people who keep their palaces clean are paid a living wage.”

"The Mayor of London, parliament, and other employers agree that workers in London should receive at least £7.85 an hour. The Royal Household can clearly afford this for its cleaning staff," he added.

The PCS union has established an online petition appealed to Minister for Culture Jeremy Hunt to ensure that the cleaners working at the Royal Households will be paid the London living wage.

Responding to the online petition, ministry spokesman said: “the Government provides around £15 million ($23.5 million) a year to help pay for the running costs and upkeep of the Royal Palaces, but decisions on how this money is allocated are a matter for the Palace authorities.”