BBC: US President George W Bush has warned of the dangers he says are posed by Iran, in a speech in its Gulf neighbour, the United Arab Emirates.
Mr Bush said Iran threatened the security of all nations and should be confronted "before it's too late".
In a speech in Abu Dhabi on the latest leg of a Middle Eastern tour, he also urged the region to embrace democracy.
Meanwhile the UN's atomic watchdog said Iran had agreed to clear up questions about its past nuclear activities.
The statement by the IAEA said Tehran would provide details in the next four weeks.
'Human capital'
Mr Bush's address in Abu Dhabi was described by his aides as the keynote speech of his regional tour.
He told delegates at the Emirates Centre for Strategic Studies and Research (ECSSR) that more open societies would foster the Middle East's immense "human capital".
He said there had been advances in the region, but also setbacks.
Without fair elections and freedom of speech, "you cannot expect people to believe in the promise of a better future", he added.
Mr Bush said spreading freedom and democracy was the best way to defeat radicalism. Confront Iran danger early – Bush >>>
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