WASHINGTON — World powers agreed Monday to toughen U.N. sanctions against Iran after the Islamic Republic failed to accept by the weekend deadline a proposal aimed at resolving the crisis over its nuclear program, the State Department said Monday.
"We are disappointed that we have not yet received a response from Iran," State Department spokesman Gonzalo Gallegos said. "We have no choice but to pursue further measures against Iran."
The decision by Britain, China, France, Germany, Russia and the United States came after a senior Iranian general warned that if attacked, Iran "easily" could block the Strait of Hormuz, the Persian Gulf passage through which 40 percent of the world's petroleum supplies are shipped.
The Iranian threat and the world powers' agreement to seek new sanctions seemed to dash the hopes for a breakthrough that rose after the Bush administration, in a policy reversal, participated last month for the first time in direct talks with Iran on its nuclear program.
The U.S. and its allies think that Iran, which concealed its program from international inspectors for 18 years, is seeking nuclear weapons. Iran says its program is only for peaceful purposes, and it's defying U.N. Security Council demands to suspend uranium enrichment, the process that produces fuel for nuclear power plants and weapons.
Iran already has been slapped with three rounds of U.N. sanctions, including asset and visa freezes, and the European Union is poised to finalize additional steps as early as Wednesday that go beyond the U.N. measures.
The world powers haven't discussed specific measures that would be included in a new sanctions resolution. Russia and China favor more modest measures than the Bush administration and the West Europeans do.
Top diplomats from the six world powers decided in a telephone conference call to pursue additional sanctions after Tehran missed the deadline to accept a confidence-building offer aimed at starting negotiations on its nuclear program's future.
Iranian nuclear negotiator Saeed Jalili told European Union foreign-policy chief Javier Solana by telephone that Iran would give him a formal response in writing on Tuesday, Gallegos said.
Under the "freeze for a freeze" offer, which Solana presented to Jalili at last month's talks in Geneva, the world powers wouldn't seek new U.N. sanctions for six weeks if Iran didn't add new machines, known as centrifuges, to the roughly 3,500 it now operates at its enrichment plant in Natanz.
During the six-week period, both sides would discuss the form of formal negotiations and a package of political, economic and security incentives that are being offered to Iran to suspend its enrichment work.
The new EU sanctions would include discouraging government-export credits to finance trade with Iran and the inspection of cargo moving to and from Iran, a European diplomat said. He spoke on the condition of anonymity because the European measures haven't been finalized.
In March, the U.N. Security Council called on countries to inspect cargo in aircraft and vessels owned by Iran Air Cargo and the Islamic Republic of Iran Shipping Line for banned items, which include material that could be used in Iran's nuclear and missile programs.
State-run Iranian news media gave upbeat reports on the impasse Monday. The Islamic Republic News Agency quoted a Foreign Ministry spokesman as denying that any deadline was set for acceptance of the offer and saying that Iran intends to "continue (an) exchange of views with the West on its peaceful nuclear plan."
The state-run media also carried an announcement by the commander of Iran's Islamic Revolutionary Guards Corps, Maj. Gen. Mohammad Ali Jaafari, about the testing of a new indigenously designed anti-ship missile with a range of nearly 200 miles.
In the past, however, some similar Iranian claims have proved to be exaggerated, and Iranian photos last month of what Tehran claimed was a simultaneous launch of four ballistic missiles turned out to have been doctored.
Jaafari was quoted as warning that if Iran is attacked, it would use the new missile and other means to close the Strait of Hormuz.
"Enemies know that we are easily able to block the Strait of Hormuz for an unlimited period," state radio quoted him as saying. "The strait and vessels are in range of our various weapons."
Jaafari's threat appeared aimed at the United States and Israel, which say that while they want to resolve the nuclear dispute diplomatically, they aren't foreclosing the use of military force to prevent Iran from developing a nuclear arsenal.
(Warren P. Strobel contributed to this article.)
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