British Premier Gordon Brown says he would not rule out a nuclear strike against Iran over its nuclear standoff, if diplomacy failed.

Brown, who analysts believe has stepped back from shoulder-to-shoulder relations with the US since taking office in June, said Britain was part of an 'international alliance' aiming to stop Iran's nuclear program, AFP reported on Sunday.

"While nothing should be ruled out, it is important to say that the sanctions that we are placing on Iran are having some effect," he claimed.

Brown described the US as the country's most important ally adding that Washington plays an absolutely essential role in Britain's foreign policy.

Washington and its allies have stepped up rhetoric against Iran to intimidate the country into abandoning its nuclear program.

However, the Islamic Republic has repeatedly emphasized nuclear weapons have no place in its defensive doctrine.

The UN nuclear watchdog has recently said there is no evidence supporting the West's allegations against Iran, an announcement that outraged Zionist officials.

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