MONTREAL (Reuters) - Montreal-area workers who assemble Airbus's smallest jet on Sunday rejected a tentative agreement with the planemaker by 68%, the union said in a statement.

The deal would have given the estimated 1,300 workers a raise of more than 20% over five years. Airbus is trying to grow output of its smallest commercial jet to a combined 14 per month at assembly plants in Quebec and in Alabama to help lower costs of the 110- to 130-seat plane.

(Reporting By Allison Lampert in Montreal; Editing by Chizu Nomiyama)