If you've ever dreamed of renting a bijou pied-a-terre in central London then you may need to think again: average rents in some well-heeled areas of the capital now top £5,000 a month, making them off limits to all but the super-wealthy.

According to new research, a home in London's most desirable SW1 postcode - including Westminster, Belgravia and Knightsbridge - will set you back around £6,171 a month, while over in Soho and Mayfair, a place to crash will cost you on average £5,493 a month.

This works out to £65,000 a year, nearly three times the average £26,000 annual salary, according to a survey by estage agent ludlowthompson.

A tale of two cities: a dearth of affordable housing in the capital has seen rents sky-rocket, with the average monthly rent in SW1 now £6,171 \ Jeff Blackler/Rex Features

And a separate study by the London Central Portfolio shows these astronomical prices won't be coming down anytime soon: the appetite for high-profile high-end property, such as One Hyde Park, saw rental costs in Knightsbridge increase by 9.5% in the last year.

A place to lay your weary head in Knightsbridge now costs on average £1.27 a week per square foot, which, let's face it, isn't very large.

And if you're wondering who can afford these bonkers prices then you'll probably hit a brick wall there, too. London's wealthiest tenants are a secretive bunch. According to the London land registry, only 12 out of the 76 new owners of apartments at One Hyde Park are real people. The rest are held in the name of corporations registered in offshore tax havens.

Pied a terre: rental costs in Knightsbridge - home of One Hyde Park - have gone up 9.5% in the last year alone \ View Pictures/Rex Features

Director of ludlowthompson Stephen Ludlow said: 'The West End, and areas like Sloane Square, Kensington and Knightsbridge, have some of the highest rents of anywhere I know. Rents have been pushed to astronomical levels by high net worths, oligarchs and other members of the global jet set competing to live in a very limited area of London.

'These tenants are determined to live in those few areas that hold as much cachet in Moscow, Jeddah and New York as they do with the average Londoner.'

Gold dust: rental prices in central London have been pushed up by oligarchs and members of the global jet set competing to live in a relatively small area in the capital's most desirable postcodes \ Alex Segre/Rex Features

He added: 'Wealthy foreign buyers who own properties in these areas rarely rent them out. This has reduced the pool of homes available to renters and has contributed to sharp rental price increases.'

As for the rest of us, it appears to be a tale of two cities. According to Shelter, more than half of Londoners don't believe they will ever be able to afford a property of their own, while two-thirds of renters are struggling to meet their monthly expenditures.

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