An expected deal to sell Vauxhall to a French car giant must include a commitment to the long-term future of plants in the UK, a union leader says.
Len McCluskey, general secretary of Unite, said thousands of Vauxhall workers at Ellesmere Port and Luton had endured a "nerve-wracking" few weeks.
General Motors is set to announce on Monday it will sell Vauxhall and Opel to the PSA Group, which makes Peugeot and Citroen models.
Mr McCluskey said: "Over the weekend, the chief executives of both General Motors and the PSA Group have spoken to me to outline their plans.
"Unite will ensure that these are communicated to our members at the earliest opportunity so that we can end this nerve-wracking period for these loyal workers, and move forward on how to safeguard our sites.
"So while initial discussions with the PSA Group have been relatively positive, our priority now is to ensure a long-term future for our plants and the tens of thousands of workers depending on them.
"We will also be urging the Government to stay at the table, just as the French and German governments do, to provide full support for our auto workers through this deeply unsettling time."
Business Secretary Greg Clark has said Vauxhall workers had no reason to fear for their jobs.
The deal is expected to be announced at a press conference in Paris.