Moscow has declared that the fuel swap deal mandates a fresh look at the Iran nuclear programme, effectively curbing the U.S. push for sanctions.

Russia has upped the United States in a diplomatic tug-of-war over Iran's nuclear programme. While Washington was busy getting Moscow and Beijing on board for tougher sanctions against Teheran, the Kremlin quietly orchestrated a deal between Iran, Turkey and Brazil for swapping Iranian low-enriched uranium for fuel rods for use in a medical reactor. The deal has taken the wind out of the U.S. sails.

Russian President Dmitry Medvedev had set up the deal in the course of his recent interactions with the leaders of Brazil and Turkey. In April Mr. Medvedev discussed the proposal with President Luiz Inacio Lula da Silva on the sidelines of a BRIC summit in Brazil. Shortly afterwards the Russian leader pursued the initiative in Ankara, where he travelled last week from Damascus, which is closely allied to Teheran. A day after Mr. Medvedev returned from Turkey he played host to Mr. da Silva who stopped over in Moscow on his way to Teheran to put final touches to the proposed fuel swap arrangement.

Speaking after his talks with the Brazilian President, Mr. Medvedev pointedly urged Iran to respond to the Brazilian-Turkish initiative, describing it as “the last chance before the U.N. Security Council takes its decision”.

Predictably, the U.S. was quick to dismiss the Teheran swap deal as Iran's delaying tactics that would not derail “strong” sanctions Washington claimed to have agreed upon both with Moscow and Beijing.

However, Moscow has declared that the fuel swap agreement does make a difference. Mr. Medvedev welcomed the Teheran accord as a step towards finding “a politico-diplomatic solution to the problem of Iran's nuclear programme”.

Russia's Foreign Minister Sergei Lavrov told U.S. Secretary of State Hillary Clinton on Tuesday that while Moscow was still committed to “the understanding in principle” on the draft Security Council resolution on new sanctions, the swap agreement dictated the need to take a fresh look at the Iran problem.

“It is necessary now to analyse in the most detailed way the situation that has shaped up in the wake of the Teheran declaration, above all, from the point of view of urgent action Iran must take to implement it, first of all, by making an official application to the IAEA [International Atomic Energy Agency],” Mr. Lavrov said.

Moscow has therefore told Washington that getting Teheran to honour the swap deal had a higher priority than adopting new sanctions and if the U.S. did not support the deal it could be held responsible for its possible failure.

“An agreement on acceptable ways of implementing the initiative of Brazil and Turkey would help create a favourable atmosphere for resuming political-diplomatic efforts to resolve the Iranian nuclear problem in its totality,” Mr. Lavrov told Ms Clinton.

Mr. Lavrov also made it clear that U.S. plans to take unilateral sanctions against Iran could be an obstacle to the passing of the U.S.-pushed Security Council resolution. He voiced Moscow's “concern” over U.S. planned sanctions describing them as “going against the principle of the supremacy of international law as laid down in the U.N. Charter.”

In its push for more talks with Teheran, Russia has received support from China, which said on Wednesday that the efforts by Brazil and Turkey will “aid the process of peacefully resolving the Iran nuclear issue through dialogue and negotiations”. Washington will also have to factor in strong opposition to new sanctions from Brazil and Turkey, both non-permanent Security Council members.

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