
He will be granted audience with His Majesty the King to be sworn in at 5 pm Sunday.
Tej is a former ambassador to the United States.
His first mission is to fly to Cambodia on Monday to conduct a bilateral talk over the dispute over a 4.6 square kilometre tract near the Preah Vihear temple.
Born on November 25, 1943, Tej has a long diplomatic career.
He joined the Foreign Ministry in 1969 as the second secretary of the Department of Information.
He became the Thai ambassador to China in 1986.
In 1990, he became the Thai ambassador to the United Nations and 1996, he became the ambassador to France and Permanent Representative of Thailand to UNESCO.
He made his way to the post the ambassador to the United States in 2000.
Former prime minister Anand Panyarachun Saturday welcome the appointment of former ambassador Tej Bunnag as the foreign minister.
He said it was the government's luck to have Tej as the foreign minister.
"The government is fortunate to have Tej as the foreign minister. He lifts the government image," Anand said.
Anand said Tej has good knowledge and background and an outstanding foreign ministry official.