Dinh Viet Thang, Director of the CAAV, said Monday that the Pakistani aviation authorities have confirmed that they would verify and respond soon. The Pakistanis consider "this lesson an experience so they will not conceal [anything] and will act transparent," he said.

Pending the Pakistani response, all the 12 pilots working in Vietnam have been suspended. The 12 are part of 27 Pakistani pilots licensed to work in the country. The other 15 have left Vietnam after finishing their contracts.

The CAAV’s request to verify qualifications was made following reports that Pakistani authorities have suspended 262 pilots on suspicion of using fraudulent licenses. The fraud came to light during investigations into a Pakistan International Airlines (PIA) plane crash in May that killed 97 people.

A total 262 out of 860 Pakistani pilots had reportedly hired somebody else to take the license examination on their behalf and were not qualified to operate an aircraft, initial investigations found.

Thang explained further that the licenses issued by Pakistan are real but "the process of issuing them could be problematic."

He said the suspension would not affect flight schedules of the carriers involved because they have other pilots on their rooster that can fill in.

Foreign pilots go through a four-round testing process as regulated by the Transport Ministry to get a license to work in Vietnam. The license is valid for five years, while the practicing certificate is valid for one year.

If they have a valid license, the pilots have the right to apply for work for Vietnamese carriers. If they move to another country, they have to abide by documentation and qualifications required by that country.

The CAAV has also begun to conduct a license review of more than 1,200 foreign pilots in Vietnam that is set to be completed by July 31.

Thang said the overall review was necessary to ensure aviation safety, not just because of the fact that many Pakistani pilots have used fake licenses.

On May 22, PIA flight 8303, an Airbus, crashed when landing at the Jinnah International Airport in Karachi in southern Pakistan, killing 97 people. Pilot error has been blamed for the tragedy.

On Saturday, Transport Minister Nguyen Van The asked the CAAV to ground the Pakistani pilots working in Vietnam pending review of their qualifications.

Vietnam's aviation market has six domestic players: Vietnam Airlines, Vietjet, Jetstar Pacific, Vietnam Air Services Company (VASCO), Bamboo Airways, and newly-licensed Vietstar Airlines, a military-run company.