US Democratic vice presidential nominee Joe Biden never said Israel would have to come to terms with a nuclear Iran, his spokesman says.

According to Haaretz newspaper, Israel's Army Radio cited Senator Biden as telling Israeli officials three years ago that sooner or later 'they would have to reconcile themselves to the reality of a nuclear-armed Iran'.

"This is a lie peddled by partisan opponents of Senators [Barack] Obama and Biden and we will not tolerate anyone questioning Senator Biden's 35-year record of standing up for the security of Israel," Biden press secretary David Wade said in a statement.

The report that was widely circulated in Israel also said that the Delaware senator had expressed doubt about the effectiveness of economic sanctions against Iran's nuclear program.

Western countries accuse Tehran of pursuing a military nuclear program and under such pretext seek to portray the country as a threat to regional and global security.

This is while the UN body responsible for monitoring Iranian nuclear activities -- the IAEA -- has confirmed that Tehran enriches uranium-235 to a level of 3.7 percent, a rate consistent with the construction of a nuclear power plant. Nuclear arms production requires an enrichment level of above 90 percent.

Under pressure from Washington and its allies, the UN Security Council has intervened in Iran's nuclear case and has so far imposed three rounds of sanctions against the country.

The Obama-Biden camp recalled an earlier remark at a July 9 Senate Foreign Relations Committee hearing, where Biden said, "Iran's acquisition of a nuclear weapon would dramatically destabilize an already unstable region and probably fuel a nuclear arms race in the region. It is profoundly in our interest to prevent that from happening."

CS/BGH