Airbus SE said it had “serious concerns” about the timetable for the trial in its dispute with Qatar Airways over allegedly defective paint on its marquee A350 airliner, accusing the carrier and the country’s regulator of “foot-dragging” to provide the required documentation.

The planemaker said that Qatar Airways would need to “take urgent steps to fill in the gaps in its disclosure” if the trial was to go ahead as scheduled in June 2023, according to documents filed by Airbus ahead of a court hearing in London on Friday. Separately, Airbus said in a statement that documentation from Qatar’s Civil Aviation Authority about the reasons for the grounding of the A350 jets is still not forthcoming.

Airbus and Qatar are embroiled in an unusually public dispute over the degradation of surfaces of the A350 wide-body jets purchased by the Gulf airline. Airbus insists that the degradation is not a safety risk, while Qatar is seeking compensation for the grounding of the jets, saying that operating them isn’t safe. The spat culminated in Airbus canceling a giant order that Qatar had placed for the smaller A321 model, saying the airline’s refusal to take delivery of A350s gave the planemaker the right to withdraw other agreements with the Gulf carrier.

In its own filing to the court, Qatar said that Airbus had asked for access to 1 terabyte worth of documentation and that the airline would need six weeks to produce the material due to technical limitations. The airline is also seeking an order at Friday’s hearing to gain access to Airbus Chief Executive Officer Guillaume Faury’s communications, asking for the executive and another Airbus executive, general counsel John Harrison, to be named as so-called custodians.

The airline, the first customer to take the A350 aircraft when it entered service, also accused Airbus and the European aviation regulator, EASA, of collusion “at the highest levels,” saying that correspondence between the manufacturer and EASA showed how Airbus tried to encourage the regulator to take the planemaker’s line, Qatar said in its court filing. 

Responding to the allegations, Airbus said it followed “all relevant procedures,”, including what it called “normal and proper” involvement of EASA as the governing civil aviation authority. EASA said separately that it coordinated with Airbus “to a limited extent only” on EASA’s so-called lines-to-take document.