US President Barack Obama said Monday the United States and Russia should lead the way in preventing nuclear proliferation by restarting negotiations to cut their atomic arsenals.

"I think it's important for the United States and Russia to lead the way on this," Obama told his first news conference.

He added that he has told Russian President Dmitry Medvedev "it is important for us to restart the conversations about how we can start reducing our nuclear arsenals."

With such a push, he said, "we then have the standing to go to other countries and start stitching back together the non-proliferation treaties that, frankly, have been weakened over the last several years."

Secretary of State Hillary Clinton told her Senate confirmation hearing on January 13 that the new administration would renegotiate the Strategic Arms Reduction Treaty (START) expiring December 31.

Clinton said the new administration "will have a very strong commitment to START treaty negotiations" which made little progress under George W. Bush's outgoing team.

State Department negotiators said there was no breakthrough in talks in Moscow in December for a follow-on agreement to replace START-1.

They said a proposal on START from the previous administration focused on limiting nuclear warheads, but Russia wanted to open up the negotiations to limits on conventional forces and US plans for a missile shield in eastern Europe.

Clinton also pledged to bolster the nuclear non-proliferation treaty (NPT) that the Bush administration has been accused of neglecting.

Obama raised the issue of proliferation after he declined to speculate when asked if he knew of a country in the Middle East which has nuclear weapons.

"What I know is this: that if we see a nuclear arms race in a region as volatile as the Middle East, everybody will be in danger," he said.

Israel is widely believed to be the only nuclear power in the Middle East, with around 200 nuclear warheads, but has a policy of neither confirming nor denying that.

The Jewish state has refused to sign the nuclear Non-Proliferation Treaty or allow international surveillance of Dimona nuclear plant, in the southern Negev desert.

The United States, Israel and European allies fear Iran is building a nuclear bomb under the cover of a uranium enrichment program. Iran insists its program is peaceful.

Analysts fear a nuclear arms race in the region if Iran produces a bomb.