DETROIT (Reuters) - Auto parts supplier American Axle & Manufacturing Holdings (AXL.N: Quote, Profile, Research) on Tuesday said contract talks with the United Auto Workers union aimed at settling a three-month-old strike had stalled since Sunday.

The Detroit-based supplier, which relies on General Motors Corp (GM.N: Quote, Profile, Research) for about 80 percent of its sales, said negotiations were snagged on two issues: health-care benefits and supplemental unemployment benefits.

American Axle made the statement in an update on contract talks. A spokesman for the UAW had no immediate comment.

About 3,650 UAW-represented workers have been on strike at five American Axle plants in Michigan and New York since late February.

The work stoppage has shut down much of GM's North American production of trucks and large SUVs since the automaker relies on American Axle to supply components for those vehicles.

GM last week offered $200 million to help American Axle fund buyouts and other one-time payments to remaining workers in exchange for their speedy ratification of a contract that would give the supplier the sharply lower hourly wages it says it needs to compete.

American Axle said the two sides had made progress on "numerous issues" in contract talks over the past weekend.

"There are very few remaining issues separating the parties from reaching agreement," the company said. "Unfortunately, negotiations have stalled since late Sunday over two issues: health-care benefits for actively employed (workers) and supplemental unemployment benefits."

American Axle said the UAW had asked for a signing bonus of $5,000 for each of its workers under a new contract and had asked for one-time buyouts of up to $140,000 for American Axle workers who agree to leave the supplier's payroll.