Spirit AeroSystems, a key supplier to Boeing, is set to reopen next week after members of the International Association of Machinists voted Thursday to ratify a tentative labor agreement and end a week-long strike.

Members voted 63% in favor of the four-year agreement, according to vote results announced Thursday. It's the first new contract that the union members at Spirit have had in 13 years. A previous 10-year deal was extended during the pandemic.

The union had put the company's previous offer up to a vote earlier this month. The prior offer from the company included a 34% pay increase, a 14.7% increase in retirement benefits with a new 401k match, voluntary Sunday overtime, and increased time off, according to the union. But rank and file members rejected that offer with 79% of members voting no, and 85% voted to strike, the union said.

A new tentative deal was reached earlier this week, which the union said was a significant improvement over the rejected deal in wages, prescription drug coverage and overtime rules.

"Our membership clearly said the original offer was unacceptable by rejecting it soundly. The committee returned to the table to address their concerns," said Jason Baze, the union's lead negotiator in the talks.

The company said it welcomed the vote and would begin ramping up operations in preparation for the resumption of work next week.

"We listened closely to our employees and brought forward a fair-and-competitive offer," said Spirit CEO Tom Gentile. "With its approval by our IAM-represented employees, we look forward to getting back to the important work of delivering quality products to our customers."

Boeing did not immediately respond to a request for comment on the vote.

The 6,000-worker strike was the latest problem for Boeing. It has halted deliveries of numerous plane models in recent years, including the 737 Max, which had problems with the fuselage that Spirit assembled.

The fuselage problem, discovered in April, was not serious enough to force in-service planes to be grounded. But it stopped deliveries of Boeing's bestselling jet while the company addressed the problem.

Spirit had been struggling in the wake of Boeing's various woes in recent years. Its last profitable year was in 2019. It has lost nearly $2 billion since then. Boeing continued to build the 737 Max even during its 20-month grounding following two fatal crashes. That helped keep Spirit and other major suppliers alive.

- CNN's Vanessa Yurkevich contributed to this report