The action against India follows weeks of DOT restrictions against Chinese airlines.

The U.S. government on Monday restricted charter flights from India, accusing the nation of “unfair and discriminatory practices” by violating a treaty governing aviation between the two countries.

Air India Ltd. has been making flights to repatriate its citizens during the travel disruptions caused by the Covid-19 outbreak, but also has been selling tickets to the public, the Transportation Department alleged.

At the same time, U.S. airlines have been prohibited from flying to India by aviation regulators there, the DOT said in its order. The situation “creates a competitive disadvantage for U.S. carriers,” the agency said in a press release.

Air India is advertising a schedule that is more than half of pre-virus operations, the department said. “The charters go beyond true repatriations, and it appears that Air India may be using repatriation charters as a way of circumventing” that nation’s flight restrictions, the U.S. agency said.

The order becomes effective in 30 days, the department said.

Indian airlines must apply to the DOT for authorization before conducting charter flights so that it can scrutinize them more closely, it said. The department will reconsider the restrictions once India lifts restrictions on U.S. carriers.

The action against India follows weeks of DOT restrictions against Chinese airlines after the U.S. agency accused that nation of unfairly banning American carriers in the wake of the virus. On June 15, the U.S. announced it would agree to allow four flights a week from China after it allowed the same number by U.S. carriers.

Attempts to reach Air India and the Indian embassy in Washington after business hours were unsuccessful.