The Civil Aviation Authority of Nepal (CAAN) has suspended two employees of the air traffic controller department for "carelessness", the aviation body's spokesperson Jagannath Niroula told India's Press Trust of India (PTI) on Sunday.
Nepal's CAAN on Sunday wrote to the Director General of Civil Aviation of India (DGCAI) to probe why the Air India plane suddenly descended to about 15,000 feet from 19,000 feet.
"We have written to DGCAI requesting them to evaluate the occurrence and take action as deemed and inform us accordingly," CAAN spokesman Jagannath Niroula told Reuters.
On Friday, an Air India and a Nepal Airlines aircraft came close to collision mid-air but the warning systems alerted the pilots which averted the disaster, PTI reported on Sunday.
The Nepal Airline's plane was coming to Kathmandu from Kuala Lumpur, Malaysia and the Air India plane was coming to Kathmandu from New Delhi.
(Reporting by Gopal Sharma in Kathmandu and Urvi Dugar in Bengaluru, Editing by Louise Heavens)