Business secretary Lord Mandelson has pledged to do "everything possible" to save Vauxhall and thousands of UK jobs ahead of a visit to the company's Luton plant today.
Ahead of his meeting with union officials, local MPs and company managers Lord Mandelson stressed the Government's "commitment to continued Vauxhall production in the UK."
He added: "I want workers at both Luton and Ellesmere Port to know that we are doing everything possible to secure a long-term commercial future for Vauxhall."
Lord Mandelson said that he, his officials and the Department for Business were in 'constant contact' with the US and German governments, General Motors in the United States, GM Europe and the interested bidders "to ensure Britain’s interests are fully represented."
Mandelson added: "Luton produces the award winning Vauxhall Vivaro van and soon Ellesmere Port will build the new Astra.
"The Luton plant represents nearly a fifth of the UK light commercial vehicle market. Vauxhall is an excellent and very popular UK brand. Continued Vauxhall production remains a top priority for this government."
Vauxhall employs about 4500 people in the UK.
The sale of Vauxhall/Opel continues to be shrouded in mystery. Although Magna International was named as preferred bidder last month, persistent rumours that the deal is not progessing smoothly have been fuelled by GM's admission that it is now negotiating with China's BAIC and Belgian investment company RHJ International.
Len McCluskey, Unite's assistant general secretary, said it was vital that the uncertainty about the plant's future was ended.
"Workers at the Luton plant are extremely worried for their futures," he said. "We need to make progress on an investor in GM Europe so that we can safeguard this plant, but it has to be the right buyer with the right vision, and a pre-requisite of any sale must be that UK jobs are protected."