France, Germany and Great Britain say Iran could face serious consequences if Tehran follows through on a threat to resume processing uranium for nuclear fuel. The tough talk is supported in Washington.
The Europeans say they are ready to walk away from negotiations with Iran if Tehran makes good on its threat to resume nuclear activities, leaving open the possibility of some kind of international sanctions.
In a letter to Iran's chief nuclear negotiator, they warn of negative consequences if Iran lifts a six-month suspension and starts processing uranium once again. In London, British Prime Minister Tony Blair said the obvious next step would be to take the matter to the United Nations for possible action.
Tehran says it will use the processed uranium to fuel a nuclear energy plant. But the United States has long questioned why an oil-rich country would need nuclear power, suggesting Iran's real intent is to develop nuclear weapons.
At the White House, spokesman Scott McClellan said Washington was told in advance about the letter to Tehran. He said the White House has been very supportive of the efforts made by Britain, France and Germany to resolve the dispute.
"We continue to support those efforts," he said. "Those efforts are ongoing at this point. But let me point out, Iran has a long history of hiding its nuclear activity. For some two decades, Iran hid its nuclear activities from the international community."
He said Iran made a deal with the Europeans to suspend uranium processing activities while negotiations are underway. The White House spokesman stressed it is time for Tehran to live up to its international obligations.
"The Europeans have made it clear that they support referring Iran to the Security Council if Iran breaks the agreement and starts some of those nuclear activities again. And that has been our position as well," he added.
A short time later, Secretary of State Condoleezza Rice said she hopes Iran will drop its threat to resume nuclear work and thus enable the talks with the Europeans to get back on track.
"The Security Council always remains an option should the Iranians not live up to their obligations, but we are still hopeful that they will recognize where they are," she said.
Secretary Rice spoke during an appearance before a Senate Committee.