Feb 1 (Reuters) - Air Transat flight attendants rejected a new tentative agreement with the Canadian leisure carrier, the union said on Thursday, fueling fears of a strike even as the airline tries to cash in on booming travel demand.

About 82% of the votes cast were against the new agreement, rejecting Air Transat's proposal for the second time, CUPE, the union representing 2,100 cabin crew members at the airline, said.

Members also voted in favor of renewing a strike mandate that had expired on Jan. 23, authorizing the union to call for one if an agreement is not reached on time.

Air Transat did not immediately respond to a request for comment.

In the past two years, unions in the aerospace, construction, airline and rail industries have advocated for higher wages and more benefits amid a tight labor market

Flight attendants are urging an end to the industry practice of not compensating them for the time spent during boarding and waiting at the airport before and between flights.

Remuneration for hours worked on the ground before takeoff and after landing as well as the question of onboard staffing were the main sticking points, CUPE said.

(Reporting by Shivansh Tiwary in Bengaluru; Editing by Krishna Chandra Eluri)