Anxious air travellers can now rest easy with the threat of a WestJet strike seemingly at an end.

The Calgary-based airline and the Air Line Pilots Association have agreed to a settlement process through the Federal Mediation and Conciliation Service. Both sides have agreed to mediation — and if required, final and binding arbitration.

"I think the most important news tonight is that the threat of strike action has been removed for WestJet guests. WestJet guests can now continue to book and travel in absolute confidence around their trip," said WestJet CEO Ed Sims from Calgary International Airport Friday night.

Earlier this month, WestJet's pilots voted 91 per cent in favour of walking off the job. They were legally eligible to go on strike as of May 19, but the pilots committed not to disrupt travel plans for passengers over the Victoria Day long weekend as a goodwill gesture.

WestJet has been negotiating with the pilots union over a new working contract for months. The sticking point for the union was the Calgary-based airlines' latest venture — the ultra-low-cost carrier Swoop.

The airline initially planned to staff the discount carrier with non-company pilots in order to keep costs low. Swoop pilots would be hired from overseas and paid less than WestJet's staff pilots. The union's position is that only WestJet pilots should fly the airline's fleet, including those of its subsidiaries.

After a tense week of negotiations, sources tell CBC News, WestJet agreed to let union-represented pilots fly all WestJet planes — including Swoop — but wages and working conditions are still being negotiated.

Neither party can walk away

Sims declined to comment on the specifics of the negotiations, but said the issues surrounding Swoop will "be part of the terms of the arbitration agreement."

Neither party can walk away from the table, Sims said. Both WestJet and the union will continue negotiations, which will ultimately conclude in binding arbitration determined by the third-party arbitrator.

WestJet CEO Ed Sims said Friday the financial damage to the airline can be counted in the 'tens of millions,' which does not include the impact on the company's share price. (CBC)

"We would like a settlement reached as soon as possible," Sims said. "I think at our most optimistic, in the next few weeks and ideally no later than the end of June."

Operating under the threat of a strike has been damaging to the airline — both financially and in terms of its reputation. Sims said the losses can be counted in the "tens of millions of dollars," which doesn't include the effect on WestJet's share price.​