British Airways has won a High Court injunction to stop the latest strikes by its cabin staff.
The BBC reports the decision was based on a technicality and whether Unite followed rules in contacting its members with strike result details.
The first of four five-day walkouts had been due to begin at midnight, but will not go ahead following Mr Justice McCombe's decision.
The union has said it will appeal against the injunction.
The first strike had been scheduled to begin on Tuesday, ending on 22 May, with the three further strikes planned to begin on 24 May, 30 May and 5 June.
BA had argued in court that Unite failed to follow the correct procedures in notifying its members of the result of the ballot.
The airline also successfully won an injunction against strikes over Christmas last year.