Thai Princess Chulabhorn has resigned as a special ambassador of the World Health Organization because of a dispute over a law barring people infected with AIDS from entering Thailand, officials said Saturday.

"Her Royal Highness does not want to do anything to offend the law," said Chotima Pathmanand, director of the Chulabhorn Research Institute which sponsors research and information on the Acquired Immune Deficiency Syndrome.Chotima said the princess tendered her resignation to WHO last Monday after WHO notified the institute that it was unable to support an international congress on AIDS starting Monday and sponsored by the institute.

WHO said it had to withdraw its support because Thailand has refused to allow people infected with the AIDS virus to enter the country under a 1985 law.

Princess Chulabhorn, the fourth child of King Bhumibol Adulyadej, was appointed WHO special envoy last year. A trained chemist, the princess has traveled widely to observe AIDS treatment and to spread information about the disease, which is virtually always fatal.

The upcoming conference was planned to expand knowledge about the disease in Thailand.

"The CRI itself does not ban AIDS-infected people from attending the conference," Chotima said. "Our activities are trying to help AIDS patients."

He said the institute was non-political and had to obey Thai law.