American Airlines pilots have voted overwhelmingly to allow their labor union to call a strike while the carrier said talks for a new contract are getting close to a conclusion.

Pilot strikes are rare and would require permission from the federal National Mediation Board. The vote doesn’t mean a decision to call a strike would happen immediately.

More than 96% of American’s pilots participated in the vote and 99% of them voted to allow the union to call a strike, the Allied Pilots Association said Monday.

The APA called the strike authorization vote in March as talks for a new deal dragged on. American Airlines CEO Robert Isom had said the airline was ready to raise pilot pay to match rival Delta Air Lines, whose pilots approved a four-year deal earlier this year with 34% raises and other improvements.

“Today marks a proud milestone in our pilot group’s unity and resolve and an important step on our path to securing the contract we have earned and deserve — one that prevents management from operating at a discount to our competitors and includes our ‘must have’ quality-of-life priorities,” APA’s president Capt. Ed Sicher wrote to pilots Monday.

A spokeswoman for American said the carrier believes a deal is “within reach” and that a “handful” of issues are left to complete.

“The finish line is in sight,” she said in a statement. “We understand that a strike authorization vote is one of the important ways pilots express their desire to get a deal done and we respect the message of voting results.”

Including higher 401(k) contributions, at the end of a potential four-year deal at American, a captain flying narrow-body planes would make $475,000 at the top of the scale while the most senior captains of wide-body planes would make $590,000 per year, based on a recent contract proposal.

Pilot contract talks have been difficult throughout the industry, including at American, United Airlines and Southwest Airlines as pilots seek not only increases in pay but quality-of-life improvements such as better, more predictable schedules as travel demand improves from the pandemic.