The positions of Washington and Moscow on the Iranian nuclear issue "have never been so near," said U.S. Ambassador to Russia John Beyrle?in Moscow?on Wednesday.

Beyrle told the Ekho Moskvy radio station that neither the United States nor Russia needs a nuclear arms race in the East Asia and the Middle East.

The nuclear non-proliferation treaty remains effective as long as the two sides synchronize their stances, said the ambassador, adding that otherwise current situations would be further jeopardized.

Washington was mulling over the switch from dialogue to sanction against Tehran, said Beyrle.

If Iran turned down the draft deal brokered by the International Atomic Energy Agency (IAEA), to which so far it has not responded, then one should prepare for something more serious, said Beyrle.

Under the IAEA draft deal, most of Iran's existing low-grade enriched uranium should be shipped to Russia and France, where it would be processed into fuel rods with the purity of 20 percent. The higher-level enriched uranium will then be transported back to Iran.

However, Tehran rejected a Dec. 31, 2009 deadline imposed by the U.S. administration to accept the deal and posed its own ultimatum earlier this month.

The West shall either sell nuclear fuel to Iran, or swap nuclear fuel for Iran's enriched uranium in smaller batches instead of at once as the U.N. plan requires, said Tehran.

The United States and its Western allies have been accusing Iran of secretly developing nuclear weapons under the disguise of civilian nuclear power. Iran has denied the accusation and stressed its nuclear program is only for peaceful purposes.

Discussions held on Saturday between negotiators from Iran, five permanent members of the UN Security Council and Germany on the Iranian nuclear issue in New York ended with no clear agreement.