EasyJet has said it plans to join rivals in launching a legal complaint to the European Commission over crippling air traffic control strikes after revealing a £25million hit from the disruption.
The airline's boss, Johan Lundgren, said he believed there was a case that EU law is bring infringed by not adequately protecting flights over France as the Commission's failure to tackle the issue is breaching freedom of movement for Europeans.
EasyJet plans to file the legal challenge next week.
It comes after Ryanair and British Airways owner International Airlines Group (IAG) recently revealed plans to join forces for a complaint to the Commission over its inaction over the strikes.
EasyJet said it had cancelled 2,606 flights in its third quarter to June 30 due largely to air traffic control strikes, which sent costs soaring by £25 million as it has had to compensate customers.
It now expects costs for the full year to rise by around 3% as a result of the disruption, which has so far been greater than seen during the whole of 2017.
Mr Lundgrun said: "It's been a challenging year so far and we estimate that this will not go away."
The group also revealed that the UK's summer heatwave could hit demand for late bookings in its final quarter, with the recent World Cup tournament also potentially putting some passengers off travelling.
But easyJet upped its full-year profit outlook to between £550 million and £590 million despite the strikes impact, thanks to strong overall demand from passengers.
Its profit guidance compares with previous guidance of £530 million to £580 million.
It said revenues in its third quarter rose by 14% to £1.6 billion, while it flew 9.3% more passengers at 24.4 million over the three months.