GENEVA: Iran and six world powers are making progress in talks aimed at ending a decade-long nuclear stand-off between Tehran and the West, but the discussions are “tough,” Iran’s foreign minister said on Thursday.

Mohammad Javad Zarif made the comment to Reuters after a first session in the two-day negotiations in Geneva, which are seeking to build on a diplomatic opening after the June election of Hassan Rowhani, a relative moderate, as Iran’s new president.

The powers hope to reach a “first step” deal to ease concern over Tehran’s nuclear program — which the West fears may be aimed at developing a nuclear weapons capability — though both sides say a breakthrough is far from certain.

Both sides have limited space for compromise, with hard-liners in Iran and hawks in Washington likely to denounce any concession they see as going too far.

“The talks went well,” Zarif told Reuters after the morning session between Iran, the United States, Britain, France, Germany, Russia and China. “I’m hopeful that we can move forward. We are making progress, but it’s tough,” he said.

Iran’s Deputy Foreign Minister Abbas Araqchi said he hoped a deal could be struck but that the sides remained far apart.

“The differences are widespread and deep. This is undeniable. And continuing the negotiations will not be an easy task, but this does not cause us to lose hope,” he said.