A move to protect London's live music scene has been launched after the closure of two of the capital's best known smaller venues.

Within two weeks, the Mayor will publish a report proposing new planning rules aimed at protecting small and mid-sized venues.

The Spitz in Spitalfields Market and Hammersmith Palais have already closed, and there are proposals to shut the Electric Ballroom in Camden, and the Astoria in Soho.

The report will follow moves to use planning law to protect small independent shops from redevelopment.

The Spitz shut last year after a rent dispute with its landlord. The club was a favourite with Russell Brand, Damon Albarn and model Lily Cole. Supporters, including singer Beth Orton and designer Giles Deacon, said the move left a "cultural void" that cannot be filled.

Hammersmith Palais shut last year to be redeveloped into an office complex.

Meanwhile, the Astoria in Soho is under threat if the Crossrail scheme goes ahead, and the Electric Ballroom is fighting plans to bulldoze it to make way for a new Tube station and shopping complex.

A spokeswoman for the Mayor said: "London is known around the world for its live music. Its reputation for a cutting edge and innovative music scene is a vital asset, nurtured by having a range of venues where live music can flourish.

"Not every venue can stay open forever, but factors such as size, location and music genre need to be taken into consideration. The Mayor has made it clear he wants London to be a city in which a range of venues, musicians and performers can thrive.

"New venues are constantly opening, like the Roundhouse, Indigo at the O2 and Rich Mix, but unique and celebrated venues such as the Spitz have closed.

"The Mayor has asked his planning advisors to develop guidance on how the future of the sector might be secured, including established venues and new developments. He has been working with the Government to ensure this issue is integrated into its forthcoming discussion paper on live music venues."