By Allison Lampert and David Shepardson

(Reuters) -Boeing’s and its largest union said on Friday that contract talks will resume on Oct. 7, as both sides seek an agreement to end a strike by around 33,000 of the planemaker’s U.S. West Coast factory workers.

Negotiators for the U.S. planemaker and the International Association of Machinists and Aerospace Workers have struggled to find common ground, recently failing to clinch an agreement on key issues in the presence of federal mediators.

“A resolution with the IAM stands as a priority for me, and our team is ready to resume mediated talks this Monday,” Boeing CEO Kelly Ortberg told employees Friday.

Reaching a deal with the IAM to end the stoppage is a priority for Boeing, as it wrestles with mounting debt, worsening cash burn and the threat of losing its investment grade rating.

The IAM’s district 751, which is negotiating the deal, said it would resume talks with Boeing Monday with assistance from federal mediators.

“This meeting is another critical opportunity to push for the priorities of our membership,” the union said.

The talks have attracted attention from U.S. President Joe Biden’s administration, with acting U.S. Labor Secretary Julie Su and her staff continuing to engage with both parties, a spokesperson said.

The strike has halted production of Boeing’s 777, 767 and its best-selling 737 MAX jet. The MAX is a key revenue-driver for the company at a time when it is struggling with weak margins in its defense business.

The strike, Boeing’s first since 2008, is the latest event in a tumultuous year for the company that began with a January incident in which a door panel detached from a new 737 MAX jet during a flight.

Boeing recently made a “best and final” pay offer featuring a 30% pay raise over four years, reinstatement of a performance bonus, improved retirement benefits and doubling of its ratification bonus to $6,000, but union leadership declined to put it to a vote.

An earlier tentative deal between Boeing and the union that offered a 25% raise over four years and a commitment that a new plane would be manufactured in the Seattle area if it were launched during the four-year agreement was voted down by more than 90% of workers in September.

Boeing shares closed up 3% on Friday.

Boeing begin furloughing tens of thousands of U.S. employees last month for one week every four weeks as it works to conserve cash.

“I want to thank everyone for their commitment to our cash conservation measures,” Ortberg said, praising employees for “such resilience to help at this difficult time, especially as we ask many of our teammates to take temporary furloughs.”

(Reporting By Allison Lampert, David Shepardson and Mike Stone; Editing by Bill Berkrot and Deepa Babington)

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