London, England (CNN) -- Union officials were going to court Thursday in London to try to stop British Airways from imposing contractual changes on its 14,000-member cabin crew.
The Unite union said it wants the High Court to issue an injunction against the British carrier to stop "unfair and unworkable" changes to cabin crew contracts.
It was unclear when the court would rule in the case.
Among the changes BA wants to impose is a reduction in the number of crew members on flights, Unite said. BA plans to impose the changes starting November 16, according to Unite.
Thursday's court action is separate from union plans to ballot its members about whether to strike over the Christmas holiday period, a Unite spokeswoman said.
Unite still plans to hold the strike ballot, possibly as early as next week, regardless of how the High Court rules, she said.
The contractual changes are part of the strike ballot, but other issues include jobs and pay, she said.