The White House warned Wednesday that Iran must not be allowed to use negotiations over its nuclear program to "stall" the world while Tehran pursues what the West fears is an atomic weapons quest.
"We cannot allow the Iranian regime to use negotiations to stall for time, hedge its bets and keep open an indigenous route to a nuclear weapon," said US national security adviser Stephen Hadley.
"If there is one thing I hope we can all agree on, it is that a nuclear-armed Iran would be disastrous for the peace of the Middle East and the world," he said in prepared remarks released by the White House.
Hadley also warned that the United States would hold "fully accountable" any country, company, extremist group, or individual who helps US foes acquire weapons of mass destruction, the AFP reported.
"The United States has made clear for many years that it reserves the right to respond with overwhelming force to the use of weapons of mass destruction against the United States, our people, our forces, and our friends and allies," he said.
"Today we also make clear that the United States will hold any state, terrorist group, or other non-state actor or individual fully accountable for supporting or enabling terrorist efforts to obtain or use weapons of mass destruction - whether by facilitating, financing, or providing expertise or safe haven for such efforts," he said.
Hadley was to deliver the speech to representatives from some 80 nations marking five years since the founding of the Proliferation Security Initiatives that aims to curb the global spread of deadly weapons know-how.
The United States and its European allies fear Iran wants to use the sensitive process of uranium enrichment to make an atomic weapon. Tehran insists its drive is entirely peaceful and has refused to freeze its efforts.
"So with many international partners, we will continue to turn up the pressure on the regime over its uranium enrichment activity -- with diplomatic isolation, implementation of UN sanctions, and with additional financial pressure," said Hadley.
The Islamic republic has thus far resisted three rounds of UN sanctions and rejected Washington's offer of negotiations if Tehran halts uranium enrichment.