The agitation has led to the cancellation of four international flights from Mumbai and Delhi.
"Four flights have been cancelled today, two each from Delhi and Mumbai," said Air India spokesperson.
"The management is also mulling the option of approaching the court against the pilots’ agitation," said airline sources.
All other Air India flights are operating as other pilots have been put on duty, said the spokesperson.
At least 200 pilots associated with to Indian Pilots Guild (IPG) on Tuesday called in sick leading to the cancellation of 13 international flights.
Striking back, Air India sacked 10 agitating pilots of the Indian Pilots’ Guild.
Meanwhile, Civil Aviation Minister Ajit Singh termed the Air India pilots' strike "illegal".
"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," said Ajit Singh.
"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.
Air India passengers vented their anger at airline staff in Delhi alleging that they were not cooperating or providing any details to them regarding their flights or other alternate flight.