A major speech by Iran's supreme leader has limited the ability of the Iranian delegation at high-level nuclear talks to make concessions with six world powers and this could scuttle chances for Tehran to reach an accord to end sanctions, diplomats said.
In a public address filled with technical detail, Ayatollah Ali Khamenei said last week Iran needs to significantly increase its uranium enrichment capacity, clashing with the powers' push for it to be reduced to minimize the risk of nuclear bombmaking, as July 20 deadline for a deal nears.
The talks with the United States, Britain, France, Germany, Russia and China are aimed at a long-term accord on Iran curbing its nuclear energy program in exchange for a gradual end of sanctions that have crippled the OPEC member's economy.
In his speech, which analysts compared in importance to a State of the Union address by a U.S. president, Khamenei said he had faith in his negotiating team led by Foreign Minister Mohammad Javad Zarif and his deputy, Abbas Araqchi.
Several diplomats close to the talks said the speech, which included many details about the nuclear programme and Iranian demands on it, came as a surprise to the Iranian delegation.
One Western diplomat said the delegation appeared "taken aback" by Khamenei's remarks at such a sensitive time in the nuclear negotiations - just ahead of the July 20 deadline for a deal. Two Iranian sources confirmed that assessment.
"In ostensibly expressing support for the Iranian negotiating team, close scrutiny of Khamenei's speech shows that in reality his remarks were aimed at severely curtailing his team's room for manoeuvre, making it effectively impossible to bridge gaps with the stance of the (six powers)," according to a Western intelligence analysis of the speech seen by Reuters.
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Khamenei's message was a reminder of the tensions within Iran's complex power elite between conservative hardliners - like him - wary of any detente with the West they fear would imperil the Islamic Revolution - and moderates who see a nuclear deal as Iran's ticket out of economically crippling isolation.
Pragmatist Hassan Rouhani's landslide 2013 election as Iranian president on a platform of improving Iran's foreign relations to revive the economy opened the door to nuclear diplomacy and a possible improvement of ties with the West. Resolving the decade-long nuclear standoff with Iran is seen as vital to allaying fears of a new war in the Middle East.
Iran and the six resumed talks in Vienna on July 2 and their negotiators continued meetings in the Austrian capital on Monday, though there was no immediate sign of any substantive progress. Western and Iranian officials have complained publicly that the sides remain far apart on all key issues in the talks.
Iran's capacity to refine uranium lies at the center of the nuclear stalemate and is seen as the hardest issue to resolve in the Vienna talks, which began in February. U.S. Secretary of State John Kerry is in Vienna to help break the deadlock. He met Zarif for a second day in a row on Monday.