American Airlines (AA, Dallas/Fort Worth) has notified the US Department of Transportation it intends to terminate its code-share agreement with WestJet (WS, Calgary) effective January 15, 2018.

The move comes after WestJet agreed to form a commercial joint venture arrangement with Delta Air Lines earlier this month. Once put in place, the JV will offer customers access to an extensive transborder route network, as well as coordinated flight schedules for new nonstop flights to new destinations and expanded codesharing. In addition, it will also offer enhanced frequent flyer benefits including reciprocal benefits for top-tier members of both airlines.

In addition, the Canadian airline has announced it will terminate its frequent flyer partnership with American Airlines effective July 31, 2018. The carriers cut benefits for top-tier members on December 20, 2017.

According to the ch-aviation schedules module, the current code-share agreement between WestJet and American Airlines covers mainly domestic flights operated by the US-based carrier out of Chicago O'Hare, Dallas/Fort Worth, Los Angeles Int'l, Miami Int'l, and Phoenix Sky Harbor, as well as services to Montréal Trudeau out of Miami and to Toronto Pearson out of Dallas/Fort Worth, Los Angeles, and Miami. It also includes a number of domestic and international services operated by WestJet mainly out of Calgary, Edmonton Int'l, Toronto Pearson, Vancouver Int'l, and Winnipeg Int'l, as well as WestJet Encore services out of Boston to each of Halifax and Toronto Pearson.