He served under President George W Bush when he acted as the main proponent of America's war on terror post 9/11 attack by al Qaeda in 2001.

Under his direction, the US forces started a campaign in Afghanistan and invaded Iraq in 2003 to decimate the terror elements that allegedly acted against the US.

In 2006, he resigned from his role amid the fallout of his decisions that led to prolonged foreign entanglement. However, he refused to accept blame.

He died surrounded by his family  in "his beloved Taos, New Mexico" on Tuesday, according to a family statement.

The reason for his death was not immediately provided.

Reacting to the news, President Bush described him as "a very good man" and an "exemplary public servant" who "never flinched from responsibility", BBC reported.

Rumsfeld was born in Chicago in 1932. His career as a businessman, bureaucrat and lawmaker spanned over several decades.

He was a long-term trusted aide of President Dick Cheney. His return to the President George W. Bush's Cabinet and appointment to run the Pentagon had come as a surprise to most people.

Rumsfeld had in the past served in the same role for President Gerald Ford in the 1970s.

He made history by serving as the youngest and the second-oldest defense secretary of the United States.

He came to Washington DC in the 1960s when he served in various positions under Richard Nixon and Gerald Ford.

Rumsfeld had to face bitter criticism when his argument that Iraqi weapons of mass destruction posed a danger to the world couldn't be proved as no such weapons were ever recovered.

According to CNN, in 2002, when he was asked about the lack of evidence for Iraqi weapons of mass destruction, he told reporters, "There are known knowns; there are things we know, we know. We also know there are known unknowns, that is to say, we know there are some things we do not know. But there are also unknown unknowns -- the ones we don't know we don't know."

In a 2011 memoir, he defended his decisions around the Iraq war but regretted some of his comments, said a BBC report.