BBC News is reporting that the talks between the carmaker Jaguar Land Rover and the UK government on a package of financial support are close to collapse.
The carmaker received what it was told was a final offer from the business department on Friday.
Jaguar has not formally rejected it, but is understood to feel that the tough conditions demanded in return for guaranteeing a loan are unacceptable.
If no financial help is provided, jobs and important investment could be cut.
The government is understood to want a right to veto management decisions, appoint its own chairman and have a say in any future redundancies at the company which employs 14,500 people.