Thomas Cook Airlines cabin crew have voted in favour of taking strike action over changes to rest breaks.
Just over 50% of those eligible voted with three-quarters (74.4%) backing the motion.
Walkouts could still be avoided with the Unite union and the company set to continue talks tomorrow with conciliation service Acas.
The company and employees are at loggerheads over changes to rest breaks. Cabin crew are now only allowed one 20-minute rest break for every 11 hours, 59 minutes worked. Before the change, they were allowed a 20-minute break ever six hours.
Unite national officer Oliver Richardson said: “We hope that the company take note of this strong vote in favour of action and works with us constructively to resolve the dispute and avoid any potential industrial action.
“We have already had exploratory talks with Thomas Cook at Acas. Over the coming days we will be approaching further Acas talks in a positive manner and trust that Thomas Cook adopts a similar approach to address our members’ legitimate concerns.”
A spokesperson for the airline said: “We’re disappointed Unite cabin crew members have taken the decision to vote.
"The safety of both our people and our customers is our top priority. We rigorously adhere to the rules around crew breaks – we haven’t changed our policy in the last two years and the Civil Aviation Authority endorses our approach.
"We’re committed to working with Unite to resolve their concerns and have already met with the conciliation service ACAS to try to find a solution."