Peugeot has come under increasing pressure to rethink its decision to close its factory in Coventry after it was criticised by 107 MPs in a letter to a national newspaper.
The politicians claimed plans to move production from Ryton to Slovakia were designed to take advantage of cheap labour.
But Peugeot denied claims it had refused to negotiate with workers or consider proposals drawn up by unions to save the plant.
The factory will next month halve its workforce to just one shift in preparation for closure next year.
It currently makes the Peugeot 206, but the vehicle is being discontinued and its successor, the 207, is to be produced in Slovakia.
A letter, published by the The Times, says that Peugeot will damage its reputation by the closure.
It was the idea of MP Jim Cunningham (Lab Coventry South) and has been signed by MPs from all parties.
Mr Cunningham said: "This reflects the strength of feeling in the House of Commons.
"Peugeot is meeting the unions next month to explain why it has rejected the business case they put together to save Ryton.
"I hope they will offer a real justification, as our concern has been that once they announced the decision to close Ryton they were unwilling to listen to other suggestions.
"The letter is designed to keep up the pressure on Peugeot."
But a spokesman for Peugeot said the unions' proposals had been reviewed "at the highest level" of the company and the unions had been sent a 38-page document explaining why it was not viable.
The company was overproducing cars at a time when the European market was stagnant, and needed to cut production, he said.
The MPs' letter says: "Peugeot plans to build a new factory in Slovakia solely to take advantage of lower wage costs and make even greater profits."
It added: "Management has refused to discuss the plan produced by the unions. We call on Peugeot to reconsider before another vital part of our manufacturing base is lost and the company's own reputation suffers irreparable damage."