About 3,200 workers at Boeing facilities in Missouri and Illinois rejected the aerospace giant’s modified labour agreement

Boeing workers who build fighter jets are planning to go on strike on Monday at midnight.

“IAM District 837 members build the aircraft and defence systems that keep our country safe,” said Sam Cicinelli, Midwest territory general vice-president for the union, in a statement.

“They deserve nothing less than a contract that keeps their families secure and recognises their unmatched expertise.”

The vote followed members’ rejection last week of an earlier proposal from the troubled aerospace giant, which had included a 20 per cent wage increase over four years.