Air Canada suspended nearly all operations on Saturday after more than 10,000 of its flight attendants walked off the job, disrupting summer travel plans for an estimated 130,000 passengers worldwide each day.

The strike, led by the Canadian Union of Public Employees (CUPE), began at 1 a.m. Eastern after negotiations with the airline collapsed. CUPE spokesman Hugh Pouliot confirmed the walkout, noting that the union had rejected the company's request for government-directed arbitration. "We're here to bargain a deal, not to go on strike," Pouliot said in an email.

According to FlightAware, 86% of Air Canada's Saturday schedule was canceled, along with 96% of Air Canada Rouge's flights. Air Canada operates roughly 700 flights daily, making the walkout one of the most disruptive labor actions in Canadian aviation in years.

The shutdown's ripple effects extend into the U.S., where Air Canada runs up to 135 flights a day from New York, Chicago, Los Angeles, Seattle and Miami to Canadian hubs. Anton Radchenko, founder of AirAdvisor, warned that "what makes this strike particularly disruptive is its timing and scope. We're in the peak summer travel window, when planes are already running at 85-90% capacity and last-minute alternatives are scarce."

The standoff centers on wages and compensation. Air Canada has offered a 38% increase in total compensation over four years, which it said would make its attendants "the best compensated in Canada." The union countered that the proposed 8% first-year raise was inadequate in the face of inflation and unpaid work when planes are not airborne.

Federal Jobs Minister Patty Hajdu, who met with both sides on Friday, pressed for progress. "It is unacceptable that such little progress has been made. Canadians are counting on both parties to put forward their best efforts," she said in a statement.

The disruption has left travelers stranded or scrambling for costly alternatives. Montreal resident Alex Laroche, 21, said his $8,000 European vacation is in jeopardy after his Saturday flight to Nice was canceled. "At this point, it's just a waiting game," Laroche said, though he added that he sympathized with attendants. "Their wage is barely livable."

Air Canada is offering full refunds through its website and app and has arranged to rebook some passengers on partner airlines, including United Airlines through their Star Alliance membership. Still, the company acknowledged rebooking may take time, as other carriers are already near full capacity.

While flights operated by regional affiliates Jazz and PAL will continue, they account for only 20% of Air Canada's network. Chief Operating Officer Mark Nasr has warned it could take up to a week to fully restore operations even after a deal is reached.