A senior U.S. diplomat says the international community needs to bring more pressure on Iran to end, what he describes as, its efforts to develop nuclear weapons. Jim Teeple has details from our Jerusalem bureau.

Nicholas Burns speaks at Herzliya conference in Herzliya, near Tel Aviv, 21 Jan 2007

"And so Iran is going to have to suffer the consequences of being an international pariah because of the Security Council sanctions," he said. "But my country does not believe we should stop there. We believe that greater pressure should be brought upon the Iranians to convince them to recalculate how they think about their nuclear program and just how valuable it is to them."

Burns says the U.S. is encouraging Russia and China not sell weapons to Iran. He says the United States is also encouraging the European Union to suspend export credits to Iran and working with international banking institutions to stop lending to Iranian state institutions, which he says are used by the Iranian government as front companies to fund terrorism.

The U.N. Security Council imposed sanctions on Iran last month for its refusal to suspend its uranium enrichment and missile programs, offering to help Iran develop a civilian nuclear power capability if it does so. The United States and the European Union say Iran is developing a nuclear-weapons program, something Iranian officials deny.

The Security Council has set a February 21 deadline for Iran to comply with its demands or face the possibility of further sanctions.

Burns says with their support for Hezbollah in last year's conflict with Israel, and through their nuclear research program, Iranian officials have come to believe they are in the ascendancy in the Middle East. But he says that is now changing and Iran is on the defensive.

"I think its defeat in the Security Council in December, and the prospect of further sanctions and the actions that my government has taken in Iraq over the past three weeks against them, the stationing of our carriers in the Persian Gulf, and now to see that even Russia and China are voting against them, Iran is no longer on the offensive, it is on the defensive and we need to keep it on the defensive," added Burns.

U.S. authorities have acted against Iran recently, stationing two aircraft carrier battle groups in the Persian Gulf, and arresting several Iranians in Iraq who U.S. officials say were assisting attacks against U.S. troops.

Burns says the United States believes in diplomacy and is not seeking a confrontation with Iran, but he says all options will remain open in the effort to get Iran to cooperate with the international community.