Boris Johnson has called on London's Premier League clubs to clean up their act when it comes to paying their staff, reports the Daily Mail.

The London mayor has written to Arsenal, Chelsea, Fulham, Spurs and West Ham after a survey revealed cleaners, catering staff and programme sellers were earning just over the minimum wage of £5.52 per hour.

In the letter, Johnson wrote: "Concerns have been raised with me about low-paid workers at London's five Premier League clubs.

Staff who are paid at a level that can reasonably sustain them tend to be more productive, loyal and committed.

It would set a superb example for your club to agree to pay your low-paid workers the London living wage and I urge you to do so."

The survey by Fair Pay Network claimed that Spurs, for example, were looking for warehouse staff for £5.75 per hour and there were vacancies at Fulham for £6.

Johnson's predecessor Ken Livingstone said a 'living wage' in London should start at £7.45 per hour.

Fair Pay Network's director, Mark Donne said: "It's offensive. Football must be one of the most unequal industries we have - an extremely wealthy sport with people servicing it who are living in poverty."