London mayoral hopeful, Labour’s Sadiq Khan, has said that every time London tenants move into new rental accommodation it costs them £3,735 upfront.

The sum, which is equivalent to six weeks’ average pay in London, was compiled by using data from London’s six biggest agents.

The figure includes letting agent fees, deposits and rent payable in advance.

The upfront cost varies from £2,662 in the Bexley and Havering boroughs to £6,080 in Kensington and Chelsea.

Khan,who is ahead in the London mayor stakes,  said the fees were exorbitant and a rip-off.

He said: “Millions of Londoners already struggling to find somewhere affordable to rent are also facing exorbitant and rip-off letting fees.”

Labour says that average letting agent fees have gone up 48% across London since 2008.

Luton MP Khan, son of a bus driver and seamstress, said that on top of fees, letting agents are asking for a deposit equivalent to six weeks’ rent and at least one month’s rent in advance.

He said the average letting agent fee charged by London’s biggest agents is £397.

The average deposit in London is £1,940 and the average first month’s rent payable in advance is £1,400.

Khan added: “People often have to move through no fault of their own, but because their rents are suddenly put up or they’re kicked out by their landlord.

“People are even having to take out loans or go into debt just to pay the huge initial costs.”

The average monthly wage in London is £2,700.

Khan has said he will set up a London-wide not-for-profit lettings agency should he become Mayor. His main rival is the Tories’ Zac Goldsmith.