Iata director-general Alexandre de Juniac told reporters in Seoul on Wednesday (29 May) he didn’t expect the aircraft to re-enter service for at least another 10 to 12 weeks, Reuters reports.

The association is reportedly planning to hold a summit in the coming “five to seven weeks” to discuss what yet still needs to happen for the 737 Max to resume flying.

The aircraft was grounded in March following a second fatal crash in just five months.

Investigations have focused on one of the aircraft’s deep-seated control systems for which Boeing is working on a software update.

“We do not expect something before 10 to 12 weeks in re-entry into service,” said de Juniac. “But it is not [in] our hands. That is in the hands of regulators.”

The US Federal Aviation Authority (FAA) has so far declined to set out a detailed timetable for the aircraft’s return to service.

“If it takes a year to find everything... so be it,” said acting director-general Dan Elwell last week.

The delay appears to confirm Tui’s worst fears, though, with it now increasingly unlikely Tui Airways’ 15 Boeing 737 Maxs will be available this summer after receiving no assurances the aircraft would be ready for the peak season.

Announcing Tui Group’s full-year results earlier this month, chief executive Fritz Joussen said he would need to know by the end of May whether its Maxs would be airworthy again.

Joussen earlier said there were two scenarios for its aircraft depending on Boeing’s advice: “July, or not at all for the summer season.”

Tui estimates the earlier date for the return of the aircraft would hit profits by 17% (€200 million); while leasing and other costs would cut earnings by 26% (€300 million) if the Max was unable to return until the winter season starts in November.

Tui has leased aircraft from at least four airlines to replace its Max flights, while another Max operator, Norwegian, has also had to replace aircraft, although none of these operate to the UK.

Both Norwegian and Tui have confirmed they will seek compensation from Boeing for the disruption arising from the grounding.