Iranian President Sheikh Hasan Rouhani said Tuesday that world powers must "seize the opportunity" of a landmark nuclear deal, saying Tehran had taken the "necessary steps" for an accord.

Iranian President Sheikh Hasan Rouhani said Tuesday that world powers must "seize the opportunity" of a landmark nuclear deal, saying Tehran had taken the "necessary steps" for an accord.

Rouhani's remarks appeared to be a response to US President Barack Obama, who on Monday said: "The issues now are -- does Iran have the political will and the desire to get a deal done?"

"Right now good progress has been made although we are some distance away from the final agreement," the Iranian president said during a meeting in Tehran with India's national security adviser Ajit Doval.

"Iran has taken necessary steps and now it's the other side's turn to seize the opportunity."

Sheikh Rouhani said that although gaps remain between Iran and the P5+1 powers - Britain, China, France, Russia and the United States plus Germany - it was up to them to close a deal.

Two deadlines for a permanent agreement on Iran's nuclear program have already been missed, requiring the talks to be extended.

Disagreements center on the "extent of nuclear activities Iran will be allowed to continue" and the timetable for the lifting of sanctions, according to media reports.