Malaysia has been downgraded to Category 2, said the sources, who did not want to be identified as they were not authorised to speak to the media.

The Civil Aviation Authority of Malaysia was not immediately available for comment.

The new rating means the air carriers from the country cannot start new services and are restricted to current levels of any existing service to the United States. The carriers would also be subject to additional inspections at U.S. airports.

(Reporting by A. Ananthalakshmi and Joseph Sipalan, editing by Louise Heavens)