Egypt's pro-democracy leader, Mohamed ElBaradei, is greeted by a young supporter before Friday prayers in Cairo, Jan. 28, 2011. (Lefteris Pitarakis/Associated Press)

As head of the International Atomic Energy Agency for 12 years — the UN group that promotes and monitors the peaceful use of nuclear energy — Mohamed ElBaradei gained considerable credibility and media exposure in the West.

In so doing, he also proved to be a thorn in the side of the George W. Bush administration.

ElBaradei was one of the first, and one of the most prominent, public officials to question the invasion of Iraq and the motivation behind it.

He led — along with Hans Mohamed ElBaradei, seen in this 2007 photo, was head of the International Atomic Energy Agency. (Hans Punz/Associated Press) Blix, who held the top job at the IAEA for the 16 years before ElBaradei — a team of UN weapons inspectors in Iraq.

Their report — released after the war was well underway — found that Iraqi strongman Saddam Hussein had no cache of nuclear weapons and posed no real military threat on that front.

At the time, the Bush administration did its best to try to discredit ElBaradei. It also tried to block his re-election as director general of the IAEA in 2005.

But he won a third term and, later that year, he and the IAEA were awarded the Nobel Peace Prize.

ElBaradei also proved to be a bit of an irritant to the Americans as they sought tougher sanctions against Iran, which the U.S. accused of attempting to develop nuclear weapons.

In February 2008, ElBaradei found that Iran had increased the transparency in its nuclear enrichment program. But he also said that it had still not shown enough evidence to demonstrate its goals were peaceful

"Iran in the last few months has provided us with visits to many places that enable us to have a clearer picture of Iran's current program," ElBaradei said at the time. "However, that is not, in my view, sufficient."

A year later, a followup report found that while there were still outstanding questions about Iran's nuclear program, the threat posed by the program had been exaggerated.

His term at the IAEA ended later in 2009. That's when he decided to turn his attention to politics in his native Egypt.

Election law changed

Prior to 2005, Egypt's president was chosen by a national referendum on a single candidate nominated by Parliament. The candidate had always been Hosni Mubarak, ever since his predecessor, Anwar Sadat, was assassinated in 1981.

In February 2005, bowing to pressure for reform, Mubarak changed the election law, allowing more than a single candidate on the ballot as well as the right to a secret vote.

Mubarak won that election with 88 per cent of the vote.

According to government figures, Ayman Nour had the most votes among the challengers, with seven per cent. He spent the next four years in jail on charges that he had forged signatures to register his new political party.

For his part, ElBaradei returned to Egypt early last year, saying he would run for president if constitutional changes allow it.

Currently, a potential candidate needs the signatures of 250 people sitting in the upper and lower houses of Parliament and municipal councils. These seats are all heavily dominated by the ruling National Democratic Party.

In a way, ElBaradei has suffered from some of the same image problems at home as Liberal Leader Michael Ignatieff here in Canada. Egyptian critics point out that he's spent most of the past 30 years abroad, building an international reputation.

He was out of the country when violence marred parliamentary elections last November and only returned when the current wave of protests picked up steam.

ElBaradei was born in Cairo in 1942, the son of Mostafa ElBaradei, a lawyer and one-time president of the Egyptian Bar Association.

At the age of 19, he became the country's top-ranked squash player. He earned a law degree in 1962 and joined Egypt's diplomatic service two years later, holding several UN-related posts until he left the service in 1980.

ElBaradei was also part of the team that negotiated the peace treaty between Egypt and Israel. He joined the IAEA in 1987.