"Four flights have been cancelled today, two each from Delhi and Mumbai," Air India spokesperson said here.
All other international flights are operating, as a contingency plan has been put in place with the available pilots, he said.
Around 200 Air India pilots owing allegiance to Indian Pilots Guild (IPG) had reported sick yesterday resulting in cancellation of at least 13 international flights.
The pilots have been protesting against rescheduling of Boeing 787 Dreamliner training. Air India management had yesterday terminated the services of 10 office-bearers of the Indian Pilots Guild, which is spearheading the strike, besides de-recognising the guild.
"The management is also mulling the option of approaching court against the pilots' agitation," airline sources said.
The Air India passengers, who are suffering due to the ongoing agitation, had heated exchanges with the airline staff in Delhi alleging that they were neither cooperating nor providing any information about their flight or any alternate flights.
Terming the agitation by the pilots as "illegal", Civil Aviation Minister Ajit Singh said the pilots should consider what the result of their action would be.
"Government is trying to bail out and giving lot of money. But part of that bailout is with (strings) that they have to perform. For the last three months Air India was doing better. Now with this action, they should consider what the result would be," he said.
"It is an illegal strike because every employee under rules is allowed to go on strike. They have... they give notice first, they should talk also. They should know Dharmadhikari report has looked at all these problems. Indian Airlines pilots, Air India pilots. The difference, the progression and those discussions before implementing we will discuss with them. Because without cooperation it would not work," he said.