Chuck Hagel, former Republican senator from Nebraska, has defended his record before a US senate committee as he seeks to calm concerns of the politicians who must confirm his nomination as the next defence secretary.

Since he was chosen by  Barack Obama, US president, Hagel has drawn stiff opposition from some members of the senate who have said he is not tough enough on Iran and has not spoken strongly enough for Israel.

"I'm on the record on many issues, but no one individual vote, no one individual quote, no one individual statement defines me, my beliefs, or my record," Hagel told the Senate Armed Service Committee in Washington DC on Thursday as the most senior Republican on the committee voiced strong opposition to his nomination.

Hagel emphasised his agreement with Obama that "all options" were on the table to deal with Iran's nuclear programme and that he would be a steadfast ally to Israel.

He also said he was committed to maintaining the US nuclear arsenal, amid questions about past remarks on denuclearisation.

Contentious exchange

Senator Jim Inhofe, the top Republican on the committee, said he was strongly opposed to Hagel serving as defence secretary.

"His record demonstrates what I view as a lack of steadfast opposition to policies that diminish US power and influence throughout the world, as well as a recent trend of policy reversals that seem based on political expediency rather than on core beliefs," Inhofe said.

Hagel was furthered grilled by John McCain, Republican senator from Arizona.

Al Jazeera's Rosiland Jordan, reporting from Washington, described it as "a very contentious exchange" between the former colleagues who had both served on the committee.

"Body language is speaking volumes right now. It's a very contentious fight", said our correspondent of the exchange between the two Republicans.

When asked about the dangers of the 22-month-long Syrian conflict spilling into neighbouring nations by McCain, Hagel responded: "no one questions the tragedy, it’s how best we [the United States] work our way through this".

If confirmed by the senate, Hagel would replace Leon Panetta as defence secretary.

However, Al Jazeera's Jordan said "there are a lot of opposition groups spending millions of dollars ... runnings ads on TV, on radio and online", to keep him from being confirmed.

Source: Al Jazeera and agencies