As the agitation by protesting pilots entered the fourth day on Friday, 12 Air India international flights were cancelled even as the Civil Aviation Minister hoped that the airline 'does not enter the ICU'.

"All our long haul flights to US, Europe, Riyadh and Jeddah have been cancelled", an Air India official said.

This has been done due to non-availability of pilots who are on mass sick leave since Tuesday, he said.

Long overhaul flights to New York, New Jersey, Chicago, Toronto, Frankfurt, London, Paris from Delhi and Mumbai were cancelled.

The national carrier has stopped bookings till May 15 on its flights to US, Europe and Riyadh.

With pilots remaining defiant, the Air India management had on Thursday sacked 9 more pilots.

Civil Aviation Minister Ajit Singh expressed hope that pilots will 'get well soon as they are sick. Air India is sick and I hope it doesn't reach ICU'.

Noting that the aviation industry and Air India are passing through a tough phase due to high price of ATF, high service tax along with Airport charges and others, Singh said he will take up the issue with Prime Minister Manmohan Singh.

On the problems facing Kingfisher, he said, "Kingfisher is a private company and they will have to sort out their problem themselves."

"Kingfisher has been in trouble since some time. They have been facing some financial problems. Air India is even worse but it (Kingfisher) is a private company so they have to mobilise the resources by themselves," Singh said.

"The main problem is how to make Air India stand on its feet, how to make it profitable and in that all the employees and their union will have to cooperate otherwise it will not stay afloat. They (airlines) have to realise that we do not raise fares for our personal interest. Air India will sink and with that all of us will sink," he said.

The Civil Aviation Minister stressed that discipline has to be maintained if Air India has to survive.

"All Unions have to rise above their personal interests. We are willing to discuss with any union but they should call off the strike especially when it is vacation time. If Air India does not stay afloat, all their jobs will be at stake," he said.

Meanwhile, around 12 Kingfisher flights were on Friday cancelled after the pilots reported sick in protest against non-payment of due salaries.

Ten flights from Delhi and two from Mumbai were cancelled after pilots did not report for work, sources said.

Pilots have been protesting since Thursday against non-payment of their due salary. Sources said a section of Kingfisher pilots have got their due salary, especially the co-pilots but the Captains have not been paid.

According to the pilots, they were assured by the management that their salary for the month of January will be paid by May nine but it did not happen due to which they started reporting sick.

17 Kingfisher flights were cancelled on Thursday due to the stir. Kingfisher Chairman Vijay Mallya had assured the staff in his May 5 communication to them that their January salaries will be remitted from May 9.

In April, the Kingfisher management had said it would pay employees' December salaries between April 4 and April 9 in a phased manner, but some of the employees received their salaries as late as around April 24, the sources said.

Kingfisher Airlines has been facing financial troubles for almost a year now. The airline, which never made a profit since its inception in May 2005, reported a net loss of Rs 444.26 crore in the December quarter. It suffered a loss of Rs 1,027 crore in 2010-11 and has a debt of Rs7,057.08 crore.

Due to paucity of funds, the air carrier now operates only 110 flights a day with a fleet of 20 aircraft as against 400 flights per day last year with 66 planes.

The airline had a 6.4 per cent market share in March, and was ranked below the budget carrier GoAir, which cornered 7.5 per cent market share in the same period.