JOIN USMathai, a 1974-batch IFS officer, will assume charge from August one and will be there for a term of two years, official spokesperson Vishnu Prakash said.
After completing post graduate studies in Political Science at the University of Pune, Mathai joined the Indian Foreign Service in 1974.
He has served in Indian embassies in Vienna, Colombo, Washington, Tehran and Brussels.
As Joint Secretary in the Ministry of External Affairs in New Delhi between January 1995 to February 1998, he headed the division dealing with India's relations with Bangladesh, Sri Lanka, Myanmar and Maldives.
He also served as Indian Ambassador to Israel from February 1998 to June 2001 and was the Indian Ambassador in Qatar from August 2001 to July 2005.
He held the post of Deputy High Commissioner of India to the UK in London from August 2005 to January 2007.
Rao, who is retiring on July 31, has been appointed as India's ambassador to the United States.