WASHINGTON — US Secretary of State Hillary Rodham Clinton said Wednesday that Iran's continuing refusal to provide more information on its nuclear program has left the international community "little choice" but to impose new, tough sanctions on Teheran.In congressional testimony, Clinton said Iran's failure to accept the Obama administration's offers of engagement and prove its nuclear intentions are peaceful had given the US and its partners new resolve in pressuring Teheran to comply with international demands through fresh penalties."We have pursued a dual-track approach to Iran that has exposed its refusal to live up to its responsibilities and helped us achieve a new unity with our international partners," she told the Senate Appropriations Committee."Iran has left the international community little choice but to impose greater costs and pressure in the face of its provocative steps," Clinton said. "We are now working actively with our partners to prepare and implement new measures to pressure Iran to change its course."The US and others believe Iran is hiding nuclear weapons development under the guise of a civilian energy program. Iran insists that its intentions are peaceful.Clinton addressed the possibility that Congress may impose its own sanctions on Iran, besides those the US is seeking through the United Nations Security Council. If Congress does that, Clinton said, it should leave the administration enough flexibility to continue the separate UN track.Congressional sanctions might be tougher than any the United States could win international approval for at the UN, but the United States wants international backing for its tough stance against Iran and sees the UN penalties as a powerful symbol of world resolve against an Iranian bomb. Clinton was in Congress to present the administration's 2011 budget request for the State Department and the US Agency for International Development of $52.8 billion, which if approved by Congress would be a $4.9 billion increase over the current budget. Most of the extra money is set to support US efforts in three countries: Afghanistan, Pakistan and Iraq.Iran has formally set out its terms for giving up most of its cache of enriched uranium in a confidential document — and the conditions fall short of what has been demanded by the United States and other world powers.Washington has dismissed the document — seen by The Associated Press onTuesday — as a "red herring" and warned it would consult with itsallies on new penalties on Iran to punish it for its nuclear defiance.The document says Teheran is ready to hand over the bulk of itsstockpile, as called for under a deal brokered by the InternationalAtomic Energy Agency and endorsed by the five permanent UN SecurityCouncil members and Germany.But Iran adds that it must simultaneously receive fuel rods for itsresearch reactor in return, and that such an exchange must take placeon Iranian territory.The Iranian offer was sure to be rejected by the six powers, which havewaited for nearly six months for such an official answer.