A German court of appeal ordered pilots at the Lufthansa airline to halt their strike on Wednesday, ruling it was illegal, overturning a judgement from a lower court the day before.
The regional court of labour in Frankfurt granted an appeal by Lufthansa against the two-day strike, arguing that the industrial action was in protest at the management's restructuring strategy, which was an entrepreneurial matter.
On Tuesday, the labour court in Frankfurt had turned down management's application.
It is the first time in the long-running 18-month dispute between management and unions that such an injunction has been granted.
Lufthansa said 140,000 passengers were grounded and 1,000 flights were cancelled Wednesday on the second day of the pilots' two-day strike.
Management and the unions have been locked in a bitter dispute since April 2014 over plans to change the pilots' early retirement arrangements.