WestJet has issued a 72-hour lockout notice to the union representing its mechanics, and warns a work stoppage could happen as early as Tuesday.

The Calgary-based airline says in a statement that the decision follows an announcement of a strike vote by the Aircraft Mechanics Fraternal Association, which represents approximately 670 aircraft maintenance engineers and skilled trade groups with the carrier.

The union is currently negotiating its first collective agreement with the airline, and has warned travellers in social media posts against booking with WestJet in the near future, 鈥渁s a work stoppage may result in unwanted delays and disruptions.鈥�

Wages, outsourcing, scheduling and layoff protection have been cited by the union as issues in the negotiations.

WestJet president Diederik Pen says in the airline鈥檚 statement that the decision to issue a lockout notice wasn鈥檛 made lightly, but that the union continues to show up to the bargaining table with what he calls 鈥渦nreasonable demands and expectations.鈥�

The statement says WestJet has presented an offer to union that would make WestJet maintenance engineers the highest paid in Canada.

鈥淲ith AMFA publicly issuing a strike vote alert last week and publicly directing guests to fly with other carriers, we can鈥檛 allow the unpredictable nature and lack of progress to continue. We are left with no alternative but to issue a lockout notice in an attempt to bring this to a final resolution,鈥� Pen said in the statement.

WestJet said the 72-hour lockout notice does not mean travel disruption will occur. But it said it will take steps in the coming days to mitigate any possible impacts, such as preparing to operate a reduced schedule and providing flexible change and cancel options for customers.

The strike vote will continue until Thursday.

The Canadian Press