Day two of the nuclear summit in Washington

Washington - (NBC) - China's President Hu Jintao says he'll join negotiations to create tough, new sanctions against Iran.

That's a big deal. China's been reluctant to crack down on Iran because Iran provides about an eighth of China's oil.

The fear is if Iran develops a nuclear weapon, it could end up in hands of al Qaeda.

"They have already said publicly that if they acquired that type of weapons capability, that they would use it," said John Brennan, Assistant to the President for Counter terrorism & Homeland Security.

Tuesday, world leaders are discussing how to track down and secure all the world's nuclear material especially in vulnerable countries like India and Pakistan.

"It's like money in a bank. There's some banks where it's not well protected and there's some banks where its remarkably well protected," said David Albright of the Institute for Science and International Security.

Ukraine has agreed to give up all of its highly enriched Uranium nuclear fuel. The U.S. could bring that material here. The White House was asked whether Americans might be reluctant to store it.

"I think they'd feel far more secure knowing that that material is under safe lock and key and guarded in this country, rather than potentially floating around somewhere else," said White House Press Secretary Robert Gibbs.

The U.S. will help pay to move that uranium. No word yet on what it will cost or where it'll go.

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