Secretary of State Hillary Clinton said on Tuesday the United States was seeking tough new sanctions to "sharpen the choices that Iran's leaders face" after weekend talks failed to make headway on Tehran's nuclear program.
Iran's foreign minister and the director general of the International Atomic Energy Agency met in Vienna over the weekend but made no progress in advancing a months-old plan for Iran to ship some of its low-enriched uranium out of the country to be turned into fuel for a medical research reactor.
"So far as we are aware based on the readout of the meeting between the Iranian foreign minister and the director general of the IAEA, there was nothing new that was presented," Clinton told reporters during a meeting with a visiting European Union official.
"Iran's continued disregard for its international obligations underscores the importance of united international pressure to change its policies," she added. "The United States is working with our partners ... on tough new sanctions that will further sharpen the choices that Iran's leaders face."
The fuel plan calls for Iran to ship 1,200 kg (2,646 pounds) of low-enriched uranium to Russia and France to make fuel for a medical research reactor. Iran agreed to the offer in principle last October but later balked at it.
"We still don't have anything other than just an ongoing effort to try to influence public opinion as opposed to sitting down and providing an answer on the outstanding offer on the TRR (Tehran Research Reactor), which is many, many months old now," Clinton said.
The United States and other Western nations believe Iran's nuclear program is aimed at making atomic weapons. Tehran denies the charge, saying it wants to enrich uranium for energy production.