DETROIT (AP) – A person briefed on concession talks between the United Auto Workers and General Motors Corp. says union negotiators walked away from the bargaining table Friday night.

The person says the talks broke off when the company made proposals that the UAW considers detrimental to providing health care to retirees. He asked not to be identified because the talks are private.

The person said no new talks have been scheduled.

The breakdown comes at a critical time, just four days before GM is to submit a plan to the government to prove it can become viable and justify its government loans.

GM has received $9.4 billion in loans thus far and can get $4 billion more if the Treasury Department approves its plan.