(Reuters) - Boeing made an improved contract offer to striking workers on the U.S. West Coast on Thursday, including a 38% pay increase over four years, a union spokesperson told Reuters.

The new offer will soon be sent to more than 30,000 union workers and a vote will be held to decide whether to accept or reject it on Monday, the spokesperson said.

(Reporting by Allison Lampert; writing by Joe Brock; Editing by Leslie Adler)