Natwar Singh is a Cambridge-educated former diplomat with a leaning towards the left.
Natwar Singh was a former ambassador to Pakistan
He has been an outspoken supporter of several iconic Third World leaders such as Cuba's Fidel Castro, Egypt's Nasser and even Saddam Hussein.
Recent comments that he regretted the break-up of the former Soviet Union and opposed the US action in Iraq have put him at odds with many in the government.
However, his decision to resign from the cabinet - after claims he profited from the Iraq oil-for-food deal - will embarrass the Congress Party's Gandhi dynasty, to whom he was very close and personally very loyal.
As a former ambassador to Pakistan, he was able to tap into the goodwill created by his contacts there and push forward the nations' peace process.
His life has also seen personal tragedy. Several years ago his daughter committed suicide, shortly after his estranged Jordanian-born daughter-in-law also killed herself.
His son, Jagat, is also under investigation for the Iraq oil-for-food scandal that has caused the former foreign minister to step down.
Both men deny allegations they profited from the UN programme.
Natwar Singh was born in 1931.
He graduated from the University of Delhi. He later studied at Corpus Christi College in Cambridge and Peking University.
He joined the Indian foreign service in 1953 and served for 31 years.
He served on several important UN committees and in 1983 was appointed secretary-general of the 7th non-aligned summit in Delhi.
He was a junior minister in the cabinet under Rajiv Gandhi and became foreign minister when Congress regained power in May last year.
Congress were in opposition in 2001, when Mr Singh and the party are alleged to have colluded with Saddam Hussein's regime for financial benefit.
Natwar Singh comes from a Rajasthan royal family and his wife is the daughter of the former ruler of Patiala in Punjab - one of the richest princely states in pre-independent India.
Mr Singh has also written a number of books, including a tribute to the novelist EM Forster.