Vistara, owned by the Tata group and Singapore Airlines, currently operates more than 300 flights a day, but has cancelled scores of flights since April 1 after a number of its pilots went on sick leave.

Some of those who went on leave complained that their pay had been cut ahead of a merger with Tata-owned Air India later this year, as they struggled with growing fatigue from a busy schedule.

The company did not refer to pilot absences. But its spokesperson said the cancellations will "provide the much-needed resilience and buffer in the rosters".

Operations were scaled back mostly in the airline's domestic network and would reduce overall levels back to where they were at the end of February, the statement added.

The company said the changes would help stabilise operations for the rest of the month and beyond.

Last week India's civil aviation ministry said it was monitoring a surge in flight cancellations by Vistara and sought information on flight disruptions.

(Reporting by Rupam Jain; Editing by Andrew Heavens)