Washington  - The US Senate voted overwhelmingly Wednesday to confirm Hillary Clinton as secretary of state, clearing the way for her to take the reins of US foreign policy as President Barack Obama moves quickly to address a host of international challenges.

Following the Senate's 94-2 vote, Clinton will now begin dealing with the pressing issues of the Iranian and North Korean nuclear programmes, the Israeli-Palestinian conflict, as well as wars in Iraq and Afghanistan. She's due to arrive at the State Department Thursday morning, a spokesperson said.

Shortly after the vote, Clinton resigned as the junior senator from New York and took the oath of office.

Hillary Clinton, 61, has built up her foreign policy credentials during her eight years in the Senate, and as a former first lady and presidential candidate is well known around the world. She will now be serving her former rival for the Democratic presidential nomination after the bitter 2008 campaign. Clinton did not vote on her nomination and must immediately resign her Senate seat before joining the executive branch.

"Hillary Clinton will combine a fresh look at our foreign policy with lots of experience and the know-how to get it done," Democratic Senator Charles Schumer said. "There is no one better to do this job."

Republican Senator John McCain, who was defeated by Obama in the November 4 presidential election and sparred with Clinton on the campaign trail, backed her for secretary of state and urged the Senate to quickly vote for confirmation.

"The message that the American people are sending us now is they want us to work together and get to work," McCain said.

Obama has sought to establish a cabinet that reflects a wide range of views. Clinton is regarded as more of a hardliner on foreign policy than the president.

The Senate Foreign Relations Committee voted 16-1 last week to send her nomination to the full chamber.

Senator John Cornyn of Texas blocked a voice vote from taking place on Tuesday, raising concerns that former president Bill Clinton's overseas fundraising for his foundation could pose a conflict of interest.

When his wife, a senator from New York since 2001, agreed in December to become secretary of state, Clinton agreed to disclose the massive list of donors to his foundation and to scale back fundraising efforts abroad. Several foreign governments had contributed to his charitable causes.

Cornyn ended up voting in favour of Clinton. David Vitter, who was the lone committee member opposing Clinton, was joined by fellow Republican Jim DeMint in voting against her in the full Senate.

Meanwhile, the Senate Foreign Relations Committee voted to approve Susan Rice as the next US ambassador to the United Nations, sending the nomination to the full Senate, CNN reported. Rice served as one of Obama's chief foreign policy advisers during the campaign.

Clinton will join Defence Secretary Robert Gates, a holdover from the Bush administration, and new national security adviser James Jones as Obama's top national security team.

During her January 13 confirmation hearing, Clinton said she will advocate the application of "smart power" - a combination of diplomatic and economic influence with military strength - to meet US objectives in the world.

Clinton said the Obama administration will be committed to reaching "a just and lasting peace agreement" in the Israeli- Palestinian conflict. She defended Israel's right to defend itself while deploring humanitarian conditions in the Gaza Strip during the three-week military offensive mounted by Israel in response to rocket attacks by Hamas militants.

Signalling his intention to build on the fragile ceasefire implemented by Israel and Hamas over the weekend, Obama on Wednesday place phone calls to Middle East leaders during his first full day in office. Obama spoke with Israeli Prime Minister Ehud Olmert and Palestinian President Mahmoud Abbas, as well as with Jordanian King Abdullah II and Egyptian President Hosny Mubarak, White House spokesman Robert Gibbs said.

Obama promised to help "consolidate" the shaky truce to ensure Hamas cannot rearm - a key objective of the Israeli assault.

The last Israeli troops pulled back from Gaza on Wednesday after the offensive, which left more than 1,400 Palestinians and 13 Israelis dead.

Obama will reportedly soon name former senator George Mitchell as special envoy to the Middle East to quickly begin addressing the conflict. Mitchell served Bill Clinton's special envoy in the Northern Ireland peace process during the 1990s and has worked on the Israeli-Palestinian conflict. (dpa)