The Allied Pilots Association (APA) will join discussions between American Airlines and US Airways regarding a potential merger.
The union will join following an invitation from the unsecured creditors committee and will adhere to the existing non-disclosure agreement between American and US Airways, it says on 10 December.
The APA represents the pilots at Fort Worth-based American.
Pilots at the airline approved a new contract on 7 December that, according to analysts, allows for a deal between the two air carriers. The APA supports a merger and reiterated its position following the vote.
A US Bankruptcy Court for the Southern District of New York judge will hear a motion to approve the pilots contract on 19 December.