The Obama administration is in danger of boxing itself into a policy dead-end by refusing to recognise what a major breakthrough Brazil and Turkey have achieved with Iran over its nuclear programme.

Immediately after the three developing nations announced their very surprising deal, US Secretary of State Hillary Clinton was left without a comment and was clearly taken by surprise. But within days she had rushed to present the "elements" of a US proposal to introduce a fourth round of sanctions against Iran, in part so that she could try to show to the Senate Foreign Relations Committee that the administration was taking the lead on the Iran issue, and in part as the start of a diplomatic attack on the Turkish-Brazilian effort.

Unfortunately, Clinton has added some new terms to the "elements" that she presented, which included a unilateral shift on the part of the US that is apparently designed to make the American terms impossible for Iran to achieve. Since October 2009, when the International Atomic Energy Agency under its former director-general Mohammad Al Baradei presented Iran with the US-backed proposal for a uranium swap for fuel rods, the US has agreed that if Iran accepted the deal, it would drop its demand for sanctions. However, Clinton's new proposal is that unless Iran stops all uranium enrichment, sanctions are back on the table, even though Tehran has made a deal — albeit with other partners.

This kind of deliberate game-playing could cost the United States friends. The US will now have trouble achieving any international consensus for its fourth round of sanctions. The Russians and Chinese had shifted closer to the American position after the discovery of the secret Qom nuclear plant, but they are starting to distance themselves from America's determination to seek confrontation, despite the fact that — thanks to Turkey and Brazil — the possibility of a new engagement is starting to emerge.