VIENNA — Iran and six major powers will keep negotiating past Tuesday's deadline for a long-term nuclear agreement as they tackle the most contentious issues, including the continuation of a UN arms embargo on Iran, the big powers said.
Russian Foreign Minister Sergei Lavrov said there was "every reason" to believe a deal would be done within "a few days," and that there was an "understanding" that most of the current sanctions against Iran would be lifted.
"There is only one big problem in terms of sanctions — it is the problem of a weapons embargo," he told journalists according to Russian news agency Interfax.
He said it was important to reach agreement on this as soon as possible, saying that "ending the bans on supplies to Iran of the weapons required to fight terrorism is a very, very relevant objective."
"We are continuing to negotiate for the next couple of days," EU foreign policy chief Federica Mogherini said outside the hotel where the talks between Iran, Britain, China, France, Germany, Russia and the United States are taking place.
The spokeswoman for the U.S. delegation, Marie Harf, said the terms of an interim deal between Iran and the six would be extended through Friday to give negotiators a few more days to finish their work.
"We're frankly more concerned about the quality of the deal than we are about the clock, though we also know that difficult decisions won't get any easier with time," Harf said. "That is why we are continuing to negotiate."
The United States and its allies fear Iran is using its civilian nuclear program as a cover to develop a nuclear weapons capability. Iran says its program is peaceful.
An agreement would be the most important milestone in decades towards easing hostility between the United States and Iran, enemies since Iranian revolutionaries captured 52 hostages in the U.S. embassy in Tehran in 1979.
A deal would be an important achievement for U.S. President Barack Obama and Iran's pragmatist president Hassan Rouhani, but both leaders face skepticism from powerful hardliners at home.
It is the fourth time the parties have extended the terms of the interim deal, which was struck in November 2013 and provided Iran with limited sanctions relief in exchange for a halt to the
production of uranium enriched to a purity level of 20 percent.