Birmingham’s weak leadership means the city is set to lose key property assets such as parts of Longbridge, Edgbaston cricket ground and Pebble Mill, mayoral candidate Sion Simon has claimed.

Mr Simon, who hopes to win the Labour nomination to stand as city mayor in 2013, condemned the Government’s decision to sell off land currently owned by regional development agency Advantage West Midlands – with the proceeds going to the Treasury.

Local councils have been told they can buy the sites, but will need to pay market rates.

By contrast, Boris Johnson’s administration in London is simply to be given the assets owned by London’s development agency.

It will be free to keep them in public ownership or to sell them off and keep the proceeds to spend on new regeneration projects.

Mr Simon said: “The difference is that London has a powerful democratic voice in the form of Boris Johnson who cannot be ignored, while this government rides roughshod over Birmingham and its interests.”

It follows an announcement by the Department for Business, Innovation and Skills that 13 sites owned by Advantage West Midlands, the regional development agency, are to be sold off.

They include the site of the former BBC studio at Pebble Mill in Edgbaston and 3.7 hectares at Eastside, in Birmingham city centre, previously used by Mathew Boulton College.

The city council could buy the sites, but the Government has warned they must be sold at market value. It has ruled out “gifting” the assets to local authorities or allowing councils to defer payment.

Ministers are still considering the fate of other properties including three hectares of land surrounding Edgbaston Cricket Ground and four sites, comprising 23 hectares, at the former MG Rover plant at Longbridge.

However, they have already made it clear that they are unlikely to be handed over to local authorities or business groups at no cost.