Air India said it has resumed six India-US flights on Boeing B777 aircraft on Thursday after the plane manufacturer gave the clearance to operate them.

Air India had cancelled eight flights on India-US routes on Wednesday due to deployment of 5G internet in North America which could interfere with aircraft's radio altimeters.

US aviation regulator Federal Aviation Administration (FAA), in a fresh directive on Thursday, said radio altimeters fitted in certain types of aircraft, including B777, will not be affected by 5G services.

Subsequently, an Air India spokesperson told PTI that Boeing has cleared the carrier to operate to the US on B777 aircraft.

"Accordingly, first flight left this morning to JFK (New York). Other flights leaving in the day are to Chicago and SFO (San Francisco). Arrangements to carry stranded passengers are being worked out. Matter regarding B777 flying into the USA has been sorted," the spokesperson said on Thursday.

The Air India flights that have resumed their operations from Thursday are Delhi-New York, New York-Delhi, Delhi-Chicago, Chicago-Delhi, Delhi- San Francisco and San Francisco-Delhi.

Along with these six flights, two other flights -- Mumbai-Newark and Newark-Mumbai -- were cancelled by Air India on Wednesday.

Boeing did not respond to PTI's request for a statement on this matter.

The US aviation regulator had on January 14 said that "5G interference with the aircraft's radio altimeter could prevent engine and braking systems from transitioning to landing mode, which could prevent an aircraft from stopping on the runway".

Radio altimeter measures height of the aircraft above the ground, allowing it to do low-visibility landings. The frequency band on which altimeter works is close to that on which 5G system works.

FAA stated on Thursday that it has made progress during the last two weeks to safely reduce the risk of delays and cancellations as altimeter manufacturers evaluate data from wireless companies to determine how robust each model is.

"This work has shown some altimeters are reliable and accurate in certain 5G areas; others must be retrofitted or replaced," the FAA noted.

It stated that five altimeters have been given the clearance. Aircraft models with one of five cleared altimeters include Boeing 717, 737, 747, 757, 767, 777.

Total three carriers -- American Airlines, United Airlines and Air India -- currently operate direct flights between India and the US.

American Airlines and United Airlines have not issued any statement on how their US-India flights have been specifically impacted by the deployment of 5G services in North America.