WASHINGTON, June 19: President George Bush on Monday threatened Iran with ‘progressively stronger political and economic sanctions’ if it turned down a US offer for direct talks.

Last month, the US offered to hold direct talks with Iran along with other western allies, if it suspends uranium enrichment before the proposed talks about incentives the EU formally presented to Iranian officials on June 6. These include an offer to help Iran develop a civilian nuclear facility.

Iran says its programme is aimed at producing electricity, in compliance with the nuclear Non-Proliferation Treaty, and denies US claims that it is developing nuclear weapons.

“We hope they will accept our offer and voluntarily suspend these activities so we can work out an agreement that will bring Iran real benefits,” Mr Bush said at the US Merchant Marine Academy’s commencement ceremony. “If Iran’s leaders reject our offer, it will result in actions before the Security Council, further isolation from the world and progressively stronger political and economic sanctions,” he said. Speaking a day before he departs for Vienna for talks with European Union leaders on the Iranian dispute, Mr Bush described his offer to Iran as ‘reasonable’ and said the US and its allies would not allow Tehran to make nuclear weapons.

“I have a message for the Iranian regime: America and our partners are united,” Mr Bush said. “Iran’s leaders should see our proposal for what it is: a historic opportunity to set their country on a better course.”

While Iran was not given a precise deadline to respond to the offer, Mr Bush said on June 9 that Iran has ‘weeks, not months’ to decide whether to suspend verifiably its nuclear enrichment activities to avoid Security Council action.

Mr Bush said he had a message for the Iranian people, too. He said they deserve to have the opportunity to develop a ‘truly peaceful’ nuclear program with proper international safeguards. He said the US and Iran should build ‘bridges of understanding’ between the two countries.

“We look forward to the day when our nations are friends and when the people of Iran enjoy the full fruits of liberty and play a leading role to establish peace in our world,” Mr Bush said.

“If Iran’s leaders want peace and prosperity and a more hopeful future for their people, they should accept our offer, abandon any ambitions to obtain nuclear weapons” and comply with international rules.

“Nuclear weapons in the hands of this regime would be a grave threat to people everywhere,” Mr Bush said. “We’ve all agreed on a unified approach to solve this problem diplomatically.”