U.S. President George W. Bush holds a news conference in the Brady press briefing room at the White House in Washington DC USA on 04 December 2007. Bush discussed the latest National Intelligence Estimate about the state of Iran's nuclear program. EPA/MATTHEW CAVANAUGH Washington - US President George W Bush urged Iran on Wednesday to 'come clean' about its nuclear activities or face further international isolation. Bush said Iran should halt uranium enrichment and enter negotiations with the United States and Europe to end the dispute over Tehran's nuclear ambitions. 'The Iranians have a strategic choice to make,' Bush said....