Tehran, Iran ? Iran’s supreme leader issued a tough line on his country’s suspect nuclear program Tuesday, saying it is “irreversible” and any retreat would endanger the Islamic republic’s independence.

The confrontational tone from Ayatollah Ali Khamenei, who has the final say on all state matters, set Iran on a collision course with the West as the five permanent members of the U.N. Security Council debated how to deal with fears Tehran is seeking to develop atomic weapons.

After meeting Tuesday at the United Nations, the Security Council powers remained divided over how strong a statement to make on Iran’s nuclear program. A British-French draft demands that Iran halt all uranium enrichment, which can be used to make nuclear arms, and calls for a report within weeks on Iran’s progress toward answering questions about its nuclear program.

Russia and China, which have strong economic ties with Tehran, say the draft does not leave enough room for diplomacy and focuses too much on possible action by the council, which could impose sanctions.

The White House said the calls by Moscow and Beijing for a negotiated end to the crisis do not mean the end of U.S. hopes for a strong statement from the 15-nation council.

“That’s premature to get into that kind of discussion,” White House press secretary Scott McClellan said. “The discussions are ongoing.”

McClellan said Iran wants to divert attention from the real issue, but that “all nations understand the importance of preventing Iran from having a nuclear weapon. … This is about the regime’s behavior.”

Khamenei’s comments further dimmed already fading hopes for a compromise proposal by Moscow that called for uranium enrichment to take place entirely on Russian soil and was seen as the last chance for averting a standoff at Security Council over Iran.

Tehran has been giving conflicting signals on the proposal, announcing over the weekend that it was no longer being considered, then saying talks with Russia were still under way.

Khamenei intervened Tuesday to lay down the one of his strongest statements on the nuclear issue, apparently aimed at ending any compromising tone from moderates within the Iranian government.

He told Iranian diplomats that there would be no backing down.

“The Islamic Republic of Iran considers retreat over the nuclear issue … as breaking the country’s independence which will impose huge costs on the Iranian nation,” Khamenei said, according to state television.

“This path is irreversible and the foreign policy establishment has to bravely defend Iran’s rights,” he told the diplomats.