Top Iranian negotiator says he's hopeful but there is no guarantee that the deal is to be announced Monday. Rohani office on reports he will speak at 5:30 P.M. GMT: He will address the nation when talks are over.

U.S. Secretary of State John Kerry, EU foreign policy chief Federica Mogherini and Iran's Foreign Minister Mohammad Javad Zarif also met in Vienna on Monday afternoon, as an deal on Tehran's nuclear program inched ever closer.

Earlier on Monday afternoon, foreign ministers from the six world powers � the U.S., Russia, China, Germany, France and Britain � met in the Austrian capital to discuss the final issues that remain unresolved with regard to the unfolding deal.

With an agreement apparently looming, France's Foreign Minister Laurent Fabius said there would be a statement on the talks in the afternoon.

Iranian President Hassan Rohani was also reportedly set to address his nation at 5:30 P.M. GMT (8:30 P.M. in Israel), but his office responded to the reports, saying that the Iranian leader would only address the nation after the talks have concluded.

Speaking to reporters outside the Palais Coburg hotel, where the negotiations are taking place, Chinese Foreign Minister Wang Yi said on Monday morning that conditions are ripe for a deal, and that additional delays should be avoided.

The head of the Iranian delegation, Abbas Araghchi, said Monday morning that there were still obstacles in the talks. He emphasized that the talks have reached a decisive point, though unresolved issues still remain.

"Some issues still remain unresolved and until they are solved, we cannot say an agreement has been reached," he said, adding that he is hopeful but that there is no guarantee that the sides will manage to announce a deal on Monday.

A Western diplomat familiar with the talks told Haaretz on Sunday that he was optimistic about the possibility of reaching a nuclear agreement and announcing it on Monday.

Iran's President Hassan Rohani hinted Sunday evening at an imminent agreement, and said that he has kept his election promise to resolve the nuclear issue.

U.S. Secretary of State John Kerry and Iranian Foreign Minister Mohammad Javad Zarif, who have been in Vienna for the past 17 days, met again on Sunday to resolve the final open questions in the agreement.

After the meeting, Zarif told reporters that there is still work to be done, but added that there would be no extension of the negotiations beyond the deadline of Monday at midnight. A senior member of the American negotiating team also said that "major issues remain to be resolve."

President Rohani's statements on Sunday left almost no room for doubt that a nuclear agreement is a matter of hours. "Thank God, I have fulfilled my election promise to try and solve the nuclear crisis," Rohani said at a Ramadan fast-breaking dinner with a group of Iranian women. "We are a few steps away from the peak� even if the process stops now, we have performed our duty."

The nuclear agreement taking shape is a hefty document. The main chapter consists of 20 pages, but includes addendums of some 80 pages. Iran's Fars news agency, which has close ties to the Revolutionary Guard, quoted a source at the Iranian delegation on Sunday afternoon as saying that according to the draft deal, "all sanctions will be lifted from Iran, but temporary restrictions will remain in place for a period of time."

According to the official, all of the economic sanction and bank-related sanction will be lifted immediately after the agreement is adopted. The source said that even the embargo imposed by the UN Security Council since 2006 will be lifted, and temporary restrictions on arms trading with Iran would be placed on Iran for a period of time. According to the source, none of the clauses in the agreement deviate from the red lines presented by Iranian Supreme leader Ali Khamanei.

By Haaretz