Around 1400 jobs at Vauxhall's Luton plant hang in the balance following GM's decision to sell the majority of Vauxhall and Opel to Magna International.
While Magna has committed to keeping Vauxhall's Ellesmere Port factory open in Cheshire, it has not offered any reassurance for the Luton plant beyond 2013.
The Luton factory produces the Vauxhall Vivaro commercial van in Britain, as well as building the van for Renault in Europe.
Renault is now considering exploiting a clause in its contract with Vauxhall which could allow it to escape its commitment to Luton. It is believed that Renault is allowed to end its deal with Vauxhall in the event of a change of ownership such as the sale to Magna.
Regardless of Renault's decision, it is expected that Magna will cut jobs from the Vauxhall workforce.
Business secretary Lord Mandelson is returning to London tomorrow and it is expected to meet Magna officials to agree on the amount of taxpayer money that the government is willing to give the company. Report suggest he may offer up to £400 million.