The central Spanish region of Castilla-La Mancha is “totally bankrupt”, according to the incoming administration of the rightwing Popular party (PP), an accusation that will deepen concerns about Spain’s budget deficit.

The claim has prompted angry denials from the Socialist government.

Spain’s 17 autonomous regions and its more than 8,000 municipalities, with €150bn ($220bn) of accumulated debt between them, have become the latest worry for investors in Spain and its sovereign bonds.

Although the amount is less than a quarter of total public sector debt, regional debt has doubled since 2008. The 17 regions collectively exceeded official budget deficit limits in 2010, and appear likely to do so again this year despite repeated demands for compliance from the central government.

Catalonia, an economy the size of Portugal, says its deficit will be double the target.