SriLankan Airlines will halve its frequencies to Chennai as a result of the impact of anti-Sri Lanka protests on its bookings.
From 21 March, the airline will cut its weekly frequency on the Colombo-Chennai route from 28 to 14 services per week.
The airline says that it "has observed a drop in traffic between Chennai and Colombo due to recent developments in Tamil Nadu".
Some groups in Chennai and other cities in the Tamil Nadu state have launched protests condemning alleged violence against ethnic Tamils in Sri Lanka.
The carrier adds that its services to other Indian cities are currently not affected, and that it is monitoring the situation and "will take further action if necessary".
Innovata schedules show that SriLankan competes with airlines including Air India, Jet Airways and SpiceJet on the Colombo-Chennai route.