AP,  Washington, May 18, 2010  – The United States has agreed with China, Russia and other major powers on a proposal for ’strong’ new sanctions against Iran over its nuclear program, Secretary of State Hillary Clinton said Tuesday.

Clinton told a Senate committee that the five permanent members of the U.S. Security Council – Britain, China, France, Russia and the U.S. – and Germany would send a new draft sanctions resolution to the entire council later Tuesday, capping months of diplomatic maneuvering and painstaking negotiations.

Clinton said she spent Tuesday morning on the phone with Russian Foreign Minister Sergey Lavrov ’finalizing the resolution,’ which will be introduced in the United Nations later in the day. Details were not immediately released, but the sanctions are expected to broaden economic penalties on Iranian officials and institutions.

The agreement appeared to be a significant victory for the Obama administration, which doggedly pursued sanctions since Iran rebuffed U.S. overtures last year.

The pursuit was complicated by initial resistance from Russia and China, both of which wield veto power in the Security Council.

But in recent weeks, Russia and China have been persuaded to support at least some degree of increased pressure on Iran.

Perhaps more significantly, Clinton’s announcement to a Senate committee came just one day after Iran, Brazil and Turkey said they had agreed on a plan for Iran to swap nuclear materials.

Many believed the last-minute agreement would blunt the U.S.-led drive for a fourth round of U.N penalties on Iran.

Clinton said the agreement on a new resolution by the major powers was a rejection of Iran’s efforts to forestall penalties.

’This announcement is as convincing an answer to the efforts undertaken by Tehran over the last few days as any we could provide,’ Clinton told the Senate Foreign Relations Committee.

’We don’t believe it was any accident that Iran agreed to this declaration as we were preparing to move forward in New York,’ she said. ’With all due respect to my Turkish and Brazilian friends, the fact that we had Russia on board, we had China on board and that we were moving early this week, namely today, to share the text of that resolution put pressure on Iran which they were trying to somehow dissipate.’

U.S. and European officials had reacted skeptically to the Brazilian-Turkish-brokered proposal, warning it still allows Iran to keep enriching uranium toward the pursuit of a nuclear weapon. The deal was concluded during a visit to Tehran by Brazil’s President LuizInacio Lula da Silva who has fought against a new round of sanctions.

Both Silva and Turkish Prime Minister RecepTayyipErdogan, who was also in Tehran for the announcement, have urged the international community to support the deal.

’Historically it has been shown that those imposing sanctions are usually the ones violating the sanctions,’ Erdogan told reporters on the sidelines of a European Union meeting in Madrid on Tuesday. ’I think Iran has taken a leap forward. Now it’s in a very positive situation which should be appreciated by the international players.’

But Clinton repeated the U.S. skepticism about the agreement, saying ’there are a number of unanswered questions regarding the announcement coming from Tehran.’

’While we acknowledge the sincere efforts of both Turkey and Brazil to find a solution regarding Iran’s standoff with the international community over its nuclear program, we are proceeding to rally the international community on behalf of a strong sanctions resolution that will in our view send an unmistakable message about what is expected from Iran,’ Clinton said.

The draft is to be presented to the entire 15-member U.N. Security Council later Tuesday, U.N. diplomats said, speaking on condition of anonymity ahead of an official announcement.