July 27 (Reuters) - Union members who assemble Boeing's ( BA )

fighter jets in the St. Louis area have "overwhelmingly

voted" to reject the company's contract offer on Sunday.

Boeing's ( BA ) proposal, which was sent on Tuesday to more than

3,200 members of the International Association of Machinists and

Aerospace Workers (IAM) District 837, included a 20% general

wage increase over four years and a $5,000 ratification bonus,

as well as more vacation time and sick leave.

"The proposal from Boeing Defense fell short of addressing

the priorities and sacrifices of the skilled IAM Union

workforce," the IAM union said.

Boeing ( BA ) did not immediately respond to a Reuters' request for

a comment.

The current contract expires on Sunday following which there

is a seven-day cooling off period before a strike would begin,

the union added.

Boeing's ( BA ) defense division is expanding manufacturing

facilities in the St. Louis area for the new U.S. Air Force

fighter, the F-47, after it won the contract earlier this year.