Taipei [Taiwan], August 6 (ANI): Many flights were cancelled, some of them rerouted following China's military drills near Taiwan after US House Speaker Nancy Pelosi's visit to the self-governed island.

Korean Air, Asiana and Singapore Airlines are among the carriers who cancelled flights over a Chinese military exercise in the Taiwan Strait, reported Al Jazeera.

The move comes after Beijing cautioned carriers to avoid six "danger zones" where the People's Liberation Army is conducting drills aimed at upholding "sovereignty and territorial integrity" after the veteran United States politician defied its warnings against a trip.

South Korea's Korean Air cancelled all flights to Taiwan on Friday and Saturday, while local rival Asiana cancelled its Friday route, reported Al Jazeera.

Korean Air also moved up the schedule for its Sunday flight to Taipei by an hour, after Asiana delayed its flight by three hours on Thursday.

Singapore Airlines and its budget offshoot Scoot said they had cancelled all four flights between Singapore and Taipei scheduled for Friday and would monitor the situation for further changes, reported Al Jazeera.

Japan's ANA and Japan Airlines have continued to operate all flights as scheduled but have adjusted the route on flights to Taipei, Hong Kong and Southeast Asia to avoid the affected airspace.

Hong Kong's Cathay Pacific Airways said on Thursday it was avoiding designated zones around Taiwan, potentially adding to the duration of some flights.

Taiwan's Civil Aeronautics Administration said it guided the rerouting of 74 passenger flights in and out of the island during a four-hour period on Thursday alone, the island's Central News Agency reported.

Philippine Airlines, Taiwanese carriers China Airlines and EVA Air, and cargo carriers FedEx and United Parcel Service were still flying to the island on Friday, according to flight tracking service FlightRadar24.

China is carrying out its biggest-ever military exercises in the Taiwan Strait until Sunday, firing ballistic missiles and deploying dozens of fighter jets and warships in six areas near the island.

Beijing launched the exercises after Pelosi, the speaker of the US House of Representatives, defied warnings not to visit the self-ruled island, which the Chinese Communist Party considers territory that should be "reunified" -- by force if necessary.

Aviation safety cooperative OPSGROUP said China's military exercises would affect major routes between Southeast Asia and Northeast Asia, forcing airlines to take longer and more expensive journeys, reported Al Jazeera.

The disruption, however, is likely to pale in comparison to that caused by conflict in other parts of the world given the relatively small area of airspace involved.

For example, airlines' decision to avoid Russian airspace following the invasion of Ukraine added four hours to flight times between Finland and Japan, reported Al Jazeera. (ANI)