Former Senator Chuck Hagel has been confirmed by the US Senate as the new Pentagon chief, after four Republicans joined Democrats to approve his nomination.
The former Republican Nebraska senator was confirmed by 58-41.
Chuck Hagel will replace outgoing Defense Secretary Leon Panetta, who was confirmed by 100-0 in June 2011.
Two weeks ago, Republicans delayed a vote, questioning Chuck Hagel’s past positions on Israel and Iran, and his qualifications for the post.
But they dropped the filibuster stalling tactic, the first time it has ever been used to delay confirmation of a defense secretary, after a week-long recess.
President Barack Obama’s Democratic Party holds a 55-45 edge in the chamber, and Chuck Hagel ultimately only needed 51 votes to be confirmed.
Republican Senators Thad Cochran, Rand Paul, Richard Shelby and Mike Johanns voted in favor of Chuck Hagel’s appointment.
After the acrimonious nomination fight, President Barack Obama said he was pleased there had been at least some bipartisan support for Chuck Hagel.
“I am grateful to Chuck for reminding us that when it comes to our national defence, we are not Democrats or Republicans. We are Americans, and our greatest responsibility is the security of the American people,” said Barack Obama.
Earlier on Tuesday, Chuck Hagel, a decorated Vietnam veteran, passed a crucial procedural vote that needed the support of 60 senators.
Former Senator Chuck Hagel has been confirmed by the US Senate as the new Pentagon chief
Among the sticking points in Chuck Hagel’s nomination process was a remark he made in a 2008 book that the “Jewish lobby” intimidated decision-makers on Capitol Hill.
Republican senators also said they feared the 66-year-old Chuck Hagel would be too lax on Iran.
During his time as a senator, Chuck Hagel angered Republican party leaders when he pilloried former President George W Bush’s handling of the Iraq war.
Ted Cruz, an outspoken conservative first-term senator from Texas, recently suggested without evidence that Chuck Hagel had accepted payments from North Korea.
During his confirmation hearing in January, Chuck Hagel sought to reassure the Senate armed services committee that he was “fully committed” to preventing Iran from obtaining a nuclear weapon.
He also apologized for the “Jewish lobby” comment, saying he could not be defined by any single quote.
Chuck Hagel’s Democratic Party supporters produced other remarks and evidence they said showed he would stick to existing US policy on Israel and Iran.
The White House had warned of great risks in leaving the Pentagon without a leader at a time of budget challenges and while the US has troops in Afghanistan.
Senate Democrats blasted their colleagues for the blocking tactics, but some Republicans protested that they needed more time to weigh the nomination.
Others, including several senior Republicans on the armed services committee, said outright that they would not back Chuck Hagel.
Outgoing Pentagon chief Leon Panetta has declared today that North Korean military ambitions are a “serious threat” to the US.
In a speech made after Pyongyang carried out its third nuclear test, Leon Panetta likened the North to Iran, describing them as “rogue states”.
In New York, the UN Security Council “strongly condemned” the nuclear test.
The council said it would begin work on measures against North Korea, after UN chief Ban Ki-moon said the test was a “clear and grave violation”.
Earlier, Pyongyang said “even stronger” action might follow, saying its test was a response to US “hostility”.
Nuclear test monitors in Vienna say the underground explosion had double the force of the last test, in 2009, despite the use of a device said by the North to be smaller.
If a smaller device was indeed tested, analysts said this could take Pyongyang closer to building a warhead small enough to arm a missile.
UN sanctions on North Korea were expanded after the secretive communist state launched a rocket in December, in a move condemned by the UN as a banned test of missile technology.
North Korea’s latest nuclear test comes as senators in Washington prepare for the first votes on whether to confirm Chuck Hagel as successor to current Defence Secretary Leon Panetta.
In a farewell speech at the Pentagon, Leon Panetta said the US would continue to be tested by unpredictable regimes in years to come.
“We’re going to have to deal with weapons of mass destruction and the proliferation. We’re going to have to continue with rogue states like Iran and North Korea.
“We just saw what North Korea’s done in these last few weeks – a missile test and now a nuclear test. They represent a serious threat to the United States of America. We’ve got to be prepared to deal with that.”
Outgoing Pentagon chief Leon Panetta has declared today that North Korean military ambitions are a “serious threat” to the US
President Barack Obama, who is to make his State of the Union speech later, called the test a “highly provocative act” and called for “swift” and “credible” international action in response.
China, North Korea’s main ally and a veto-wielding member of the Security Council, summoned North Korea’s ambassador to Beijing to express its concern over the test.
Foreign Minister Yang Jiechi delivered a “stern representation”‘ to Ji Jae Ryong and expressed China’s “strong dissatisfaction and firm opposition” to the test, the Chinese foreign ministry said in a statement.
Earlier, it urged the North to honor its commitment to denuclearization and “not take any actions which might worsen the situation”.
The test was condemned by North Korea’s immediate neighbors, South Korea and Japan, while Russian Foreign Minister Sergei Lavrov called for a revival of talks on the North’s nuclear arms programme.
In a defiant message to the UN’s disarmament forum, the North said it would never bow to resolutions on its nuclear programme and blamed the failure of diplomacy on the US.
“The US and their followers are sadly mistaken if they miscalculate the DPRK [North Korea] would respect the entirely unreasonable resolutions against it,” the North’s envoy, Jon Yong Ryong, told the Conference on Disarmament in Geneva.
North Korea confirmed the test after international monitors recorded seismic activity consistent with a powerful underground explosion at 11:57 on Tuesday.
Activity had been observed at the Punggye-ri nuclear test site for several months.
State-run KCNA news agency said the test was “carried out at a high level in a safe and perfect manner using a miniaturized and lighter nuclear device with greater explosive force than previously”.
North Korea said the nuclear test was a response to the “reckless hostility of the United States”.
“The latest nuclear test was only the first action, with which we exercised as much self-restraint as possible,” the foreign ministry said in a statement.
“If the US further complicates the situation with continued hostility, we will be left with no choice but to take even stronger second or third rounds of action.”
The Vienna-based Comprehensive Nuclear-Test-Ban Treaty Organization said the “explosion-like event” was twice as big as the 2009 test, which was in turn bigger than that in 2006.
It is the first such test under new leader Kim Jong-un, who took over the leadership after his father Kim Jong-il died in December 2011.