European Union officials have called for "coordinated action and full respect" of EU state aid and internal market rules as General Motors' European units are restructured.

Following national support measures for the restructuring of GM Europe, they said that, while the efforts were welcome, there was a need to respect treaty rules, Bloomberg News reported.

GM has said Opel would need EUR3bn (US$4.1bn) in loan guarantees from EU governments in the countries where it builds cars.