The Bush administration called Iran's offer to let a watchdog agency inspect the country's nuclear facilities a stalling tactic intended to avoid UN penalties that would further isolate Tehran.
"I think they're playing games," US Secretary of State Condoleezza Rice said on Sunday on ABC's This Week.
"But obviously, if they're not playing games, they should come clean. They should stop the enrichment, suspend the enrichment," she said.
Iran's deputy oil minister played down the chance of UN action, saying punishing Tehran would send oil prices even higher.
Tehran on Saturday offered to allow inspections if the UN Security Council would turn the dispute over to its nuclear monitor, the International Atomic Energy Agency.
A report by the UN agency confirmed Iran had successfully produced enriched uranium and defied the Security Council's Friday deadline to stop the process.
Iran maintains it will not make nuclear weapons and does not need or want them. But the US, Britain and France suspect the intent of the uranium enrichment program is to make nuclear warheads.
"The international community is completely of one mind, that no one wants, needs or really can tolerate a nuclear-armed Iran in the midst of the world's most volatile region. That is the consistent view," Rice told CNN's Late Edition.
While the US and its European allies are pushing for possible penalties, veto-wielding Security Council members Russia and China have opposed the idea.
Rice said that Washington would seek a UN resolution requiring that Tehran comply with demands it stop enriching uranium.
She mentioned a resolution under Chapter 7 of the UN Charter, which can be enforced through penalties or military action.
Iran's deputy oil minister played down the idea of penalties.
"Any action like that will increase oil prices very high. And I believe that the UN or its bodies will not put any sanctions on oil or the oil industry," M.H. Nejad Hosseinian told reporters in Pakistan.
Rice, however, declared, "No one is talking about going to oil and gas sanctions." She cited potential steps such as freezing assets.
"Oh, I absolutely believe that we have a lot of diplomatic arrows in our quiver at the Security Council and also like-minded states that would be able and willing to look at additional measures if the security council does not move quickly enough," Rice told CBS' Face the Nation.
In contrast, former secretary of state Colin Powell said in an interview broadcast on Sunday in London that Iran seems to "have pretty much decided they can accept whatever sanctions are coming their way."