Iran could become a nuclear power in less than 10 years if it continues to enjoy Russian backing for efforts to acquire non-conventional weapons, a senior Israeli military official said Sunday.

"We believe it will take five to 10 years," the official told journalists on condition of anonymity, describing Iran as the "main threat against us."

Caption: A file photo taken in December 1996 shows the Bouchehr nuclear plant in the north of the Persian Gulf. During his 28 February visit to the plant, Iranian President Ali Akbar Hachemi-Rafsandjani reaffirmed Tehran's determination to master nucleaar technology. Copyright AFP

"There is a great effort to obtain non-conventional capabilities with the support of Russia," he added.

"We have to put it on the front-burner … in order to delay or to stop (the Iranian effort)," the official said, calling on the United States to pressure Russia to halt aid to Tehran.

Earlier this month the United States said it would continue to blacklist 10 Russian research centers and companies for cooperating with the Islamic republic on nuclear or missile research.

The Israeli official said he expected that Iran's Shihab-3 missile system, which has a range of 1,200 kilometres (750 miles), could be operational in one or two years and said the republic was working towards missiles with a range of 5,000 kilometres (3,100 miles).

Iran regards Israel as its arch-foe and continues to call for the destruction of the Jewish state.