BANGKOK - Thailand's government on Monday scrambled to address "significant safety concerns" by the U.N.'s International Civil Aviation Organization (ICAO) that has the kingdom's airlines facing bans on international flights.

The ICAO negative review quickly led Japan and South Korea to block charter and new flights from Thailand. There is concern other countries, including the United States, will take similar action, especially if the ICAO downgrades Thailand from Category 1 to Category 2.

A U.S. government source - who is not authorized to speak on the record - explained the ICAO report would probably trigger an audit of Thailand's aviation sector by the Federal Aviation Administration. He called the ICAO audit results a "real red flag for the FAA."

Japan and South Korea do not conduct their own assessments and usually rely on ICAO findings to take action.

Decision by Japan

Japan's Civil Aviation Bureau said that for now, no new charter flights operated by airlines registered in Thailand would be allowed to fly to Japanese airports because of concerns the carriers may not meet international safety standards.

Under particular scrutiny is the department of civil aviation, supervised by the transport ministry. Officials of the ministry and department, including Civil Aviation department Director-General Somchai Piputvat, met on Monday with Prime Minister Prayuth Chan-ocha.

The prime minister, who seized control of Thailand's government in a military coup last May when he was army chief, said he discussed the Japanese and South Korean bans on new flights with the leaders of both countries and they promised to further consider the matter.

Prayuth also stated he would use powers under Section 44 of the interim charter to rectify the problems of Thailand's airlines.

Section 44 effectively allows the junta boss to issue any orders he deems appropriate without judicial or other oversight.

“This is a national issue. The transport ministry will quickly solve the problem" because "dominos are starting to fall," transport Minister Prajin Juntong told reporters after the meeting.

Previous administrations blamed

Officials of Thailand's government, under control of a military junta since last May's coup, are blaming previous administrations for not paying heed to the problem.

"The ICAO has warned us since 2005 about our aviation management and asked us to improve our systems," Prajin said.

The ICAO has rejected the civil aviation department's enhancement plan, submitted March 2, reportedly because it proposed a two-year period to fix problems.

Critics have said Thailand's civil aviation sector suffers from frequent changes of government, corruption, complacency and incompetence.

The January audit in Thailand "revealed some safety concerns, primarily relating to air operator certification procedures," said Anthony Philbin, communications chief for the ICAO Secretary General in Montreal. "We can’t discuss any further details in light of the agreement in place between the Organization and its Member States governing the conduct and reporting of ICAO universal safety oversight audit results."

Some media reports Monday said Thailand passed only 21 out of 100 areas reviewed by auditors, garnering a lower overall score than any other ASEAN nation.

ICAO concerns

Thailand's civil aviation department did not give details of the ICAO's concerns but said additional training will be provided to its staff and airline inspections will be increased.

Industry sources said the most serious concerns involve shortcomings for safety regulations for low-cost carriers, including certifications for air operations and the transportation of hazardous goods.

On professional pilots' forums on the Internet, comments about the ICAO safety warning have prompted comments by industry workers alleging government inspectors were bribed with cash and massages to favorably sign off on paperwork.

A commentator who said he worked for a "substandard" Thai charter airline for nearly 17 months wrote he was told that executives had decided to not purchase any more parts for maintenance and he quit after refusing to fly planes that had defects.

The FAA is likely to conduct its own aviation safety assessment of Thailand that would three critical areas: airworthiness of aircraft, airman licensing and operator requirements, said a U.S. government official familiar with the procedures.

FAA downgrade

An FAA downgrade for Thailand would mean, among other things, a suspension of code share operations where a Thai carrier is the operating carrier.

Currently operated flights have not been affected by the ICAO audit.

But additional flights, including those for Thailand's mid-April Songkran festival, are now grounded. That has affected tens of thousands of tickets sold to travel agencies or individual travelers.

Travel operators said this has caused the cost of some package tours during the Songkran holiday to nearly double.

Other than the kingdom's flag carrier, Thai Airways, the ICAO safety warning is also affecting low-cost carriers Thai Air Asia X, NokScoot and Asia Atlantic Airlines.

Travel industry officials in Thailand worry the perception that the country's airlines are now unsafe could further hurt tourism. The crucial sector for the Thai economy, employing millions of people, has been beset over the past 18 months by concerns about tourists' safety and political unrest.