The Tribhuvan International Airport has been shut since 7:20am on Thursday due to dense fog, disrupting both international and domestic flights. Airport officials said it could take some time for operations to resume.

Visibility until 9:30am was limited to just 500 metres, according to the airport office. Aircraft approaching under the RNP-AR system require a minimum visibility of 1,100 metres to land, while those using the VOR-DME system need at least 1,600 metres. Departures from Kathmandu also require a minimum visibility of 1,200 metres.

As a result, several international flights bound for Kathmandu are currently holding over the Simara airspace. These include a Nepal Airlines wide-body aircraft from Doha, two Himalaya Airlines narrow-body aircraft from Dubai and Doha, a Druk Air narrow-body aircraft from Bhutan, and a Qatar Airways wide-body aircraft from Doha.

Domestic flights have also been affected. Buddha Air said operations at Biratnagar, Rajbiraj, Nepalgunj, Dhangadhi, Surkhet and Tumlingtar airports are yet to resume.

The airport office has advised passengers to contact their respective airlines for the latest updates.