Updated

The United States has downgraded the safety rating of Thailand's aviation industry in a move that could hamper operations of Thai airlines worldwide.

The Federal Aviation Administration announcement Tuesday comes after the International Civil Aviation Organization, a U.N. body which regulates international aviation standards, flagged significant concerns about Thailand's aviation safety in March.

The FAA lowered Thailand's rating to "category 2" which means its civil aviation authority is deficient in one or more critical areas or that the country lacks laws and regulations needed to oversee airlines in line with international standards.

"Thailand does not comply with International Civil Aviation Organization safety standards," the FAA statement said. It audited Thailand's civil aviation authority in July as part of its role in ensuring airlines that fly to the United States meet international standards.

Thai airlines can continue existing services to the United States but will not be allowed to establish new services.

Thailand is one of the world's top tourist destinations, and its tourism industry accounts for about 7 percent of the country's economy.

Regulators in other countries are likely to be influenced by the FAA announcement, which could lead to measures against national flag carrier Thai Airways and other airlines.

After the ICAO warning in March, Thailand's military government vowed to overhaul its civil aviation authority.