A section of Air India staff union has threatened "industrial action" if the management did not reinstate 23 cabin crew, who were derostered over the last month's Cairo flight delay episode.

The union is contemplating to launch a 'non-cooperation' drive from tomorrow to press its demands, a union leader said.

"We have written a letter to the management, stating that the derostering of all 23 cabin-crew is illegal. We want an immediate reinstatement of the derostered crew, failing which we will resort to industrial action," All India Cabin Crew Association (AICCA) general secretary, Sanjay Lazar told PTI here on Thursday.

The Air India Mumbai-Toronto flight was operated from Cairo on April 15 due to closure of European airspace due to volcanic ash. The flight was delayed by around 16 hours and it was reported that a section of the cabin crew had gone out for sight-seeing in the Egyptian capital, causing the delay.

This charge, was however, refuted by the AICCA.

The Association claims representation of around 3,000 cabin crew, including executive cadre in National Aviation Company of India Limited (NACIL).

NACIL is the holding company formed after the merger of erstwhile Indian Airlines and Air India.

"We do not rule out the possibility of striking work as well if our demands are not met," he said.

The derostering is also a 'violation' of the 1987 Agreement between the management and cabin crew, which states that the cabin crew shall not be derostered unless there is a criminal case, Lazar said.

At the same time, the management has not taken action against its two senior officials, who are directly responsible for the inordinate delay in the flight, Lazar alleged.

"Even the chargesheet issued to the crew is illegal for many reasons. The standing orders, under which the chargesheet has been issued stands null and void after the merger of erstwhile Indian Airlines and Air India," he said.