The European Commission is to scrutinise German backing for the takeover of General Motors’ European operations amid concern that planned job cuts could be influenced by political factors, hitting plants in the UK and Belgium disproportionately hard.

Signalling that she would take a tough line on the issue, Neelie Kroes, EU competition commissioner, said she would look at “the entire context” of €4.5bn (£3.8bn) in loan guarantees provided mainly by the German government to back the deal by Magna, the Canadian car parts supplier, to buy a 55 per cent stake in Opel and its UK business Vauxhall.