UNION officials have sent an open letter to General Motors demanding an end to speculation about the future of its car manufacturing plants.
Over the last few months, GM Europe president Carl-Peter Forster has been quoted at motor shows around the globe as saying Vauxhall plants, including the one in Ellesmere Port, are 'vulnerable'.
And last week he was quoted as saying that Saab's factory in Troll-hatten, Sweden, had a 'good chance' of building the next-generation Astra.
Five plants across Europe, including the Port, are vying to build the next generation Astra. A decision on which ones will land this contract is due to be made next year.
Mick Whitley, deputy regional secretary of the Transport & General Workers' Union, said: 'The unions have sent an open letter to Carl-Peter Forster about his comments. It says we feel they were unhelpful.'
He said the Swedish workers were initially invited to put in a bid for the Vectra, but failed, so had nothing to lose by bidding for the new Astra.
'We have five plants putting in a bid for three plants' work, but we feel Antwerp, Bochum (in Germany) and Ellesmere Port are the main ones.
'We are in with a good chance in the Port. But this posturing from GM is not doing any good,' added Mr Whitley.
Asked if GM might be playing the plants off against each other to drive up productivity, he said:
'There's no doubt that's what they are trying to do, to put themselves in a good position when they go to negotiate the contract.'
Mr Whitley added: 'We are just working very hard, both the in-plant unions and external unions, to secure employment for the next 12 years and more in Ellesmere Port and secure its future.'
Vauxhall Motors spokesman David Crundwell said of the Saab bid rumours: 'We have no intention of commenting on this. It's just speculation.
'Our situation has not changed. No decision on the new Astra has been made.'
He added: 'Ellesmere Port is working very well on three shifts building the present car and is also building the new Astra van, which we have yet to launch.'
Some fear that when the contracts for the new Astra are finally awarded, they could lead to the closure of one of the current European plants.
The Opel plant in Bochum is thought to be especially at risk because of its high production costs.