He succumbed to bone cancer, which he had fought since January.

Sippanont died at 1pm at Siriraj Hospital, where he was admitted early this year, his daughter Tarisa Ketuthat said.

A royally sponsored bathing rite will be held today at the Wat Benchamabopitr.

Her Royal Highness Princess Maha Chakri Sirindhorn is expected to attend and preside over today's bath-ing ceremony.

Guests are asked not to bring wreaths to the funeral.

Sippanont was the seventh child of former commander-in-chief of the Air Force, Group Captain Phraya Tayanpikhart and Khunying Thanom.

He studied physics in the US for nine years after winning a government scholarship.

He obtained a bachelor of science degree at the University of California before securing a master's and a PhD in nuclear physics at Harvard.

Sippanont taught physics at Chulalongkorn University and was deputy director of the Southeast Asian Ministers of Education Secretariat (SEAMES).

In 1974, he served as secretary-general of the Office of the Education Council and as adviser to the World Bank.

He sat on the councils of 13 local and international universities.

"He was an education pioneer and worked to push through education reforms," said Chulalongkorn University academic Amornvit Nakhonthap.

"His death means we have lost not only an educator, but a good leader," Amornvit said.

Sippanont also served as head of the National Economic and Social Development Board (NESDB).

In 1980, he served as deputy education minister, then education minister and industry minister. Sippa-nont was also a former senator.

Sippanont and his wife Amilie have three children. He is survived by his son, Tonithip, 41, and two daughters: Marina, 39, and Tarisa, 37.