A view of the meeting room before the start of a conference in Vienna February 18, 2014. [Photo/Agencies]

US to deal harshly with violators of Iran sanctions Iran ready for long term deal: FM

VIENNA - Six world powers and Iran began "substantive" talks on Tuesday in pursuit of a final settlement on Tehran's contested nuclear programme in the coming months despite caveats from both sides that a breakthrough deal may prove impossible.

Senior US and Iranian officials met separately for 80 minutes on the sidelines of the negotiations in Vienna.

Details were not given, but such bilateral talks were inconceivable before the 2013 election of Hassan Rouhani, a relative moderate, as president of Iran. US-Iranian dialogue is seen as crucial to any breakthrough nuclear agreement.

"The conversation was productive and focused mainly on how the comprehensive talks will proceed from here," a senior US State Department official said on condition of anonymity after Under Secretary of State for Political Affairs Wendy Sherman's meeting with Iranian Deputy Foreign Minister Abbas Araqchi.

Sherman headed the US delegation, while Iranian Foreign Minister Mohammad Javad Zarif and Araqchi led Tehran's negotiating team at the table with Britain, China, France, Germany, Russia and the United States.

After Sherman's meeting with Araqchi, the Iranians met on Tuesday evening with all six powers to continue talks on how to approach future negotiations, diplomats said. The discussions will resume on Wednesday roughly at 10:30 am and could run into Thursday.

"Much of the first day was focused on discussions about process for how the comprehensive talks will proceed," a senior US official said. "We made clear that every issue is on the table as part of the comprehensive negotiations, and now it's time to dig into the details and get to work."

In the evening session between Iran and the six "substantive issues began to be discussed", the US official added.

A European diplomat said no decisions had been taken yet on how the talks will proceed in the future - the six powers led by the EU foreign policy chief Catherine Ashton want to get a deal done within six months.

"We had quite detailed discussions, productive and in a positive atmosphere," the diplomat said. "But this is day one and we have at least another day."

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