The European Commission Wednesday repeated its warning to Germany that it will carefully scrutinise any state aid provided to carmaker General Motor's European arm Adam Opel to ensure it follows the European Union's strict rules on state aid.

The commission will examine indications that negotiations are taking place between a number of European governments concerning aid that is linked to the number of workers finally retained by New Opel in different countries, it said.

"The European Commission will not accept state aid that is conditional upon the implementation of a specific business plan, previously negotiated with member states, which defines the geographic distribution of restructuring measures," without allowing those businesses receiving the funds to revise their plans if necessary, said the commission's spokesman on competition matters, Jonathan Todd.

-By Carolyn Henson, Dow Jones Newswires; +32 2 741 1481; carolyn.henson@dowjones.com