The Iranian delegation presented the six world powers in Geneva on Tuesday with a PowerPoint presentation they hoped would allay international concerns enough to ease some of the economic sanctions against their country.

The United States and Iran held a bilateral meeting about the latter’s nuclear arms program on the sidelines of Tuesday’s six-party talks, which sought to prevent Tehran from producing such weapons.

The two countries first crossed the “bilateral Rubicon” during the UN General Assembly, which marked the first high-level meeting between the two countries since 1979.

Still, on Tuesday the US and Europe warned against expectations for a quick diplomatic solution at the two-day parley.

“We certainly want to make clear that no one – despite the positive signs that we’ve seen – no one should expect a breakthrough overnight,” White House press secretary Jay Carney said as he described the first day of the two-day gathering.

“Although we appreciate the recent change in tone from the Iranian government on this issue, we will be looking for specific steps that address core issues.”

In light of a conciliatory tone out of Iran, diplomats from the US, Russia, China, France, the UK and Germany entered the talks with a sense of optimism, even as they remained cautious at the end of the day.

The negotiations focused on highly technical issues beyond the knowledge of most diplomats in the room, State Department spokeswoman Jen Psaki told reporters on Tuesday as she described the Iranian presentation.

“I don’t think we characterize it as a breakthrough at this stage,” Psaki said, telling reporters to expect a more expansive assessment of their progress after the round of talks end on Wednesday.

“Having technical discussions for the first time at this level is certainly where things stand,” she added.

The Iranians came into talks publicly expressing hopes for a diplomatic framework and timelines moving forward, but did not provide the P5+1 with a proposal before talks began.

On the sidelines of the talks, Iranian Foreign Minister Mohammad Javad Zarif held a bilateral meeting with EU foreign policy chief Catherine Ashton.

Undersecretary of state for political affairs Wendy Sherman and members of the US delegation held an hourlong bilateral meeting with Iranian Deputy Foreign Minister Abbas Araqchi and his staff on Tuesday, a senior State Department official said.

“The discussion was useful, and we look forward to continuing our discussions in tomorrow’s meetings with the full P5+1 and Iran,” the official said.

An official characterized the tone of the meeting as “optimistic.”

Araqchi cautioned it was too early to say whether the Islamic Republic had made progress on Tuesday.

“It’s too soon to judge,” he said when asked whether the two sides were any closer to resolving a stalemate that has heightened the risk of a new Middle East war.

Michael Mann, a spokesman for Ashton, said while “it was useful to hear from the Iranian side what they envisage... We do need to hear more detail from the Iranian side.”

Mann told BBC Persian television that “there is still an awful lot of work to be done.

We have had a certain amount of information from the Iranian side, and we will hope to get more detail from them tomorrow.”

Earlier in the day, he tweeted that “for the first time, very detailed technical discussions continued this afternoon between [the six powers] and Iran on the Iranian nuclear program.”

A senior administration official told journalists on Monday that the White House believed the US “needs to put time on the clock” for negotiations to succeed.

“It really takes not just those of us sitting here, but it takes a whole army, virtually, of technicians to figure out a whole variety of things,” the official said.

“Now the question is, will the administration, will the Rouhani team, follow up their words with actions?” Psaki said. “That is the conversation happening on the ground.”

National Security Council spokeswoman Bernadette Meehan told The Jerusalem Post that US-led sanctions had compelled Iran to the negotiating table in Geneva.

“This administration continues to enforce a comprehensive set of international sanctions against the Iranian regime,” Meehan said.

“There is no doubt that our efforts to apply economic pressure on Iran through sanctions have gotten us where we are today – to have the opportunity to test Iranian intentions to seek an enduring diplomatic solution.”

The senior official told reporters that any sanctions relief would have to be “proportional to what Iran puts on the table,” admitting that Iran was likely to quibble with the definition of “proportionate.”

Before the meeting, Ashton said, “I hope that what we will have here is a very productive two days, an opportunity to explore both the proposals that we have put on the table, but also ideas that are coming from Iran. We have come here with cautious optimism, but a real sense of determination.”

JPost.com staff and Reuters contributed to this report.

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