— Iranian Foreign Minister Mohammed Javad Zarif says an agreement with six world powers to resolve a decade-long standoff over Tehran's nuclear program is 'possible' by end of talks Friday.
U.S. officials said late Thursday that Secretary of State John Kerry will fly to Geneva Friday to participate in the nuclear negotiations -- a last-minute decision that suggests a deal could be imminent.
Zarif told CNN Thursday he believes "it is possible to reach an understanding or an agreement before we close these negotiations tomorrow evening," adding that Tehran was not willing to suspend uranium enrichment "in its entirety."
Iran's top diplomat expressed similar optimism in an interview two days earlier with a French television network.
Iranian negotiators, led by Zarif, met the United Nations contact group Thursday in Geneva for talks that could be decisive in easing tensions over Iran's nuclear program.
This discussions started with what was described as a “good meeting” over breakfast between Zarif and the European Union's foreign policy chief, Catherine Ashton, who chairs the U.N. team.
Then, the full delegations from Iran, the five permanent Security Council members, Germany and the EU got together for a 45-minute session. They were followed by smaller group meetings throughout the day.
"We are beginning to get to more detailed discussions this afternoon," Zarif told Reuters. "I'm hopeful that we can move forward...We are making progress but it's tough."
In Washington, the White House signaled the United States was prepared to offer Iran limited relief from economic sanctions if it agreed to halt its nuclear development program and reverse part of it.
But the U.S. Congress tends to take a harder line on Iran than the Obama administration, and the chairman of the U.S. Senate Banking Committee said he would move ahead with a package of tough new sanctions on Iran after the negotiating session on its nuclear program ends in Geneva on Friday.
Talks enter 'serious phase'
An EU spokesman said the talks are entering "a serious phase.”
A senior U.S. official says the two sides are coming to understand what a “first step” would look like, after just one round of formal talks and one experts' meeting since the new Iranian government took power in July.
Officials are not providing details of an Iranian proposal presented here last month, but the senior U.S. official, who spoke on condition of anonymity, said the basic idea is to pause Iran's nuclear program, perhaps for six months, to provide time for negotiations on a long-term agreement.
In return, the official said the international community would ease some sanctions but not alter what she called the core sanctions regime.
The international community is seeking changes to Iran's nuclear program, and more transparency, to guarantee that it does not lead to the production of nuclear weapons.
Iran says it has no intention of developing such weapons, but parts of its program go beyond what experts say is needed for nuclear power and research, and it could be only months away from producing enough highly enriched uranium to build a nuclear bomb.
Zarif said last week that Iran's new government is working to dispel those concerns.
“We believe that even a perception that Iran is seeking nuclear weapons is detrimental to our security, so we will do our best in order to remove that perception,” he said.
After the first round of talks, the chief U.S. delegate, Under Secretary of State Wendy Sherman, told VOA's Persian News Network the issues are difficult and fueled by decades of mistrust, but she indicated the two sides are now working toward the same goal.
"What I have seen in Geneva is a very different approach. It is a practical approach where each country of the P5+1 and Iran fight very hard for the interests of their country. That is what we are required to do," she said. "But at the same time (we) are trying to solve a problem that we really want to solve.”
But the Obama administration is fighting a rear-guard action against some members of Congress, who want to add sanctions against Iran just as these talks are showing promise, a move officials say could destroy any chance of a diplomatic solution.
At the same time, Iran's relatively moderate president, Hassan Rouhani, also has hardliners to contend with, who are likely to oppose any concessions on the nuclear program.
Iran expert and former State Department adviser Suzanne Maloney, now at the Brookings Institution, is skeptical that there is any overlap between what the two sides will accept, particularly based on a recent speech by Iran's Supreme Leader, Ayatollah Ali Khamenei.
“While he has sought to defend the positions of the negotiators publicly, he has indicated, I think, a very strong skepticism that they'll be able to produce the kind of deal that he would accept," Maloney said.
"There does appear to be some distance between what the Iranians say publicly they want and need, in terms of sanctions relief, and what the administration seems to believe they can get away with offering,” she said.
Bridging that gap is the significant challenge the negotiators are facing here this week. They may not finish the job during these two days of talks, but they acknowledge they need to deliver a workable agreement soon, with only very limited amounts of patience on both sides.
Mark Snowiss contributed to this report from Washington.