The negotiations are going "very, very, very slowly," he said.

Grievances originally centering around the two assembly plants in Flint are now extending to other plants in Dayton, Ohio, and Indianapolis, Indiana. GM said these issues need to be resolved together for a deal to last.

"The reality is that it doesn't make much sense to settle cases on plants that have been on strike for over 30 days, only to be at risk to go on strike again at other facilities," said Gerald Knechtel, GM vice-president of North American Personnel.

Shoemaker said GM may still try to force a settlement in a relatively short amount of time.

"If we can settle these strikes in Flint, does it really make sense for them to keep losing $400 million a week and keep 180,000 people out of work," he said.

Since the strikebegan, 26 out 29 GM assembly plants in North America have been shut down, idling over 162,000 workers while GM has lost an estimated $1.2 billion in production.

Analysts said GM hopes to reach a settlement before July 13, when the company normally ends its two-week seasonal summer shutdown. As of Monday, production losses will resume, they said.

GM said in a statement that as of Monday, some 1,700 workers at the Romulus, Michigan, engine plant will return to work to build the new V-8 engine that is used in the new generation full-size pickup trucks.

"GM has an aggressive launch plan for these trucks and is sticking with that plan," the company said.

One issue holding up a deal is GM's insistence that the settlement include resolution of festering problems at parts plants in Dayton, Ohio, and Indianapolis. The UAW has threatened to strike those plants after the Flint walkouts end."It doesn't make much sense to settle plants that are on strike... only to be at risk to go on strike again at otherfacilities," Knechtel said. "All we're trying to do is remove that risk."

Knechtel said GM was very open to alternatives to avoid strikes at the other plants, but he did not elaborate. Shoemaker again rejected one alternative: A no-strike pledge.

"They can't remove the threat of further potential strikes, and they can't get a no-strike guarantee," he said.

In the unlikely event a settlement could be ratified and the Flint plants reopened by Monday, it would still take several days to a week before the parts pipeline would start to refill and some strike-idled assembly plants could resume production.

There is no sign negotiations will recess if no deal is reached this weekend.US Senate votes overwhelmingly to reiterate policy on Taiwan.