New letter to Tehran calls for a 'political commitment' at this month's Moscow talks

Tensions have spilled into the open in the run-up to the critical next round of negotiations over Iran's nuclear programme in Moscow due to start on June 17. Nerves are on edge after the disappointment in Baghdad last month, where there was no real progress, stoking anxiety over what might happen if the diplomatic process collapses.

The Iranian government went public on Wednesday accusing the EU External Action Service of dithering over preparations for Moscow, drawing a tangibly frustrated response tonight from the deputy head of that service, Helga Schmid, whose task it is to organise the talks on behalf of a six-nation group of major powers (known in Brussels as the E3+3). This is what Schmid wrote to her Iranian counterpart, Ali Bagheri:

Let me say that I am somewhat surprised by the issues raised in your recent letters. I would like to recall that during our talks in Baghdad the E3+3 presented a straightforward proposal which addresses on the one hand our key concerns over 20% enrichment activities and at the same time offers interesting opportunities for cooperation in the nuclear and other areas which would be beneficial for Iran

In Baghdad the E3+3 group, convened by Schmid's boss, Cathy Ashton, suggested that Iran suspend production of 20% enrichment, a particular proliferation concern, in return for reactor fuel, material support for nuclear safety and a resumption of the supply of parts for Iran's commercial airliner fleet.

The Iranian negotiator Saeed Jalili, Bagheri's boss, did not response directly to the proposal directly. He did say Iran could "discuss" 20% uranium but Iran wanted international recognition of its right to enrich in principle, reversing six UN security council resolutions calling for the suspension of all enrichment. Jalili did not appear ready to bargain. This is what Schmid had to say in her letter:

Unfortunately, in Baghdad Iran was not prepared to take up our suggestion to enter into discussions on the substance of the proposal.

This is a much more downbeat assessment of the talks than the one presented by Ashton at the end of the Baghdad round, but it more accurately reflects the dashed hopes of that encounter following weeks of guarded optimism in the wake of an encouraging first session in Istanbul in April.

In her letter, Schmid shows impatience with Iranian calls for more discussions on the agenda, and with Iranian complaints that Brussels has not cooperated, arguing that the time had come to talk about the substantive elements of a deal.

In and following Istanbul, we have established a clear and positive framework for a sustained process of serious dialogue. You and I had numerous phone calls and long meetings to work towards this end. Now there is a need to engage seriously on issues of substance in order to agree on concrete confidence building steps which could be implemented swiftly. We are very much hoping for a political commitment on your side.

Schmid signs off saying it should be "our common objective to achieve concrete results" and reminding Bagheri that she had asked "to speak to you today to discuss further". It is not entirely clear whether that conversation took place, but by about midnight Tehran time it did not seem to have happened.

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