(Reuters) -Workers at Spirit AeroSystems' plant in Wichita, Kansas, which makes critical structures for Boeing jetliners, will go on strike on Saturday, after rejecting a proposed four-year deal on Wednesday night, the International Association of Machinists and Aerospace Workers (IAM) said.
About 6,000 members of the IAM have voted to reject Spirit's "last best and final offer," with a strike scheduled to begin at 12:01 a.m. Central Time (0501 GMT) on June 24, the union said.
"The IAM's dedicated and hardworking membership at Spirit AeroSystems has worked without fail during tumultuous times, including a pandemic that saw everything grind to a halt. Most of our members have concluded that the company's offer is unacceptable," IAM said in a statement.
IAM and the company reached a tentative agreement last week that included additional health insurance and retirement benefits, made overtime on Sunday voluntary, and provided for up to a compounded 34% average pay increase over four years.
Spirit AeroSystems and Boeing did not immediately respond to a request for comment.
(Reporting by Valerie Insinna and Abinaya Vijayaraghavan; Editing by Tom Hogue)