President Bush says Iran has a lot of explaining to do about the scope of its nuclear activities. VOA's Paula Wolfson reports Mr. Bush says Tehran has a big choice to make.

President Bush is keeping pressure on Iran following a U.S intelligence community report that says Tehran operated a covert nuclear weapons development program until halting the effort in late 2003.

Mr. Bush says the fact that the program is not currently in operation is not as important as the disclosure that it once existed and could be resumed.

The president says Iran, which has never acknowledged a nuclear weapons program, has a lot of explaining to do. And he stresses the Iranian government has a strategic choice to make.

"They can come clean with the international community about the scope of their nuclear activities and fully accept the long standing offer to suspend their enrichment program and come to the table and negotiate, or they can continue on a path of isolation that is not in the best interest of the Iranian people," he said.

The president spoke in Omaha, Nebraska at the start of a visit designed to highlight his health care policy. But it was clear as he landed at a local airport that Iran was very much on his mind.

President Bush said Secretary of State Condoleezza Rice and White House National Security Advisor Stephen Hadley have been consulting with officials from Britain, France, Germany and Russia since the release of the intelligence assessment on Iran. He said there was unity on the need for continued vigilance.

"These countries understand that the Iranian nuclear issue is a problem and continues to be a problem that must be addressed by the international community," he said.

The White House is seeking a new round of U.N. sanctions on Iran. Critics say the new National Intelligence Estimate mitigates the need for harsh action.

Iranian President Mahmoud Ahmadinejad says the report supports Iran's assertion that its nuclear program is for energy, not weapons. He told supporters in Tehran that Iran would stand firm behind its right to obtain nuclear technology and would not retreat.