Iran and six world powers meet Friday in Istanbul for a second round of talks, amid guarded hope for progress in efforts to settle tensions over Tehran's disputed nuclear programme.
The meeting follows a first round in Geneva last month, which broke a 14-month hiatus in negotiations between the Islamic republic and the so-called 5+1 group of Britain, China, France, Russia, the United States and Germany.
The Geneva talks ended without any tangible outcome but the fact that the two sides agreed to continue the negotiations and fixed a second meeting in six weeks' time is seen as a positive sign, notably by the host Turkey, which is close to Iran and insists on a diplomatic settlement to the row.
"The resumption of the talks is a good development, but one should not expect too much on the essence," said Bruno Tertrais, an analyst at the Paris-based Foundation for Strategic Research.
Tehran has insisted its "nuclear dossier" would not be on the agenda of the Istanbul talks, in line with its long-standing policy that the country's "nuclear right" is not up for discussion.
"There will be no problem if three issues -- nuclear disarmament, non-proliferation and peaceful nuclear activities -- are discussed," Abolfazl Zohrevand, adviser of Iran's chief nuclear negotiator Said Jalili, told the ISNA agency Monday.
"If Westerners want to deal separately with the Iranian nuclear issue, Istanbul is not the right place since Iran's nuclear programme is transparent and overseen by the agency," he said, referring to the International Atomic Energy Agency (IAEA).
But EU foreign policy chief Cathrine Ashton, who will lead the 5+1 delegation at the talks, insisted on the contrary.
"I'm very clear that we are coming to discuss the nuclear issue and that is what we will do," she said last week when she travelled to Istanbul for preparations ahead of the meeting with Iran.
"Our purpose in meeting is to now look for tangible credible ways to make a move forward," she stressed.
Prior to previous talks with the world powers, Tehran has similarly insisted that its nuclear file is not up for discussion.
Western powers suspect that Iran's nuclear programme masks a drive to develop an atomic bomb.
Iran denies the charges, insisting its programme is a peaceful effort to producing nuclear energy.
But it has refused to stop uranium enrichment, prompting the UN Security Council to punish it with a fourth round of sanctions in June.
Additionally, the United States and the European Union have slapped a series of their own unilateral sanctions on Tehran.
Speaking Saturday, Iran's foreign minister and atomic chief Ali Akbar Salehi played down the sanctions and declared that the country's uranium enrichment programme was progressing "very strongly".
Washington however believes the sanctions have already started to hamper Tehran's nuclear activities.
"The most recent analysis is that the sanctions have been working... They have made it much more difficult for Iran to pursue its nuclear ambitions. Iran has technological problems that has made it slow down its timetable," US Secretary of State Hillary Clinton said last week.
Tertrais commented that the United States had not yet reached the "stage of impatience" with Iran.
"Since the summer of 2010, tensions have eased. The sanctions are beginning to be felt and there have been sabotage operations," he said, referring to reports that the United States and Israel developed a destructive computer worm to sabotage Iran's efforts to make a nuclear bomb.
The United States and Israel have not ruled out taking military action against Iran to prevent it from acquiring nuclear weapons.