An exchange of letters between US President Barack Obama and his Iranian counterpart, Hassan Rouhani, has set the stage for a possible meeting between the two at the United Nations next week.
If the two leaders meet it would be the first face-to-face encounter between U.S. and Iranian heads since Iran's 1979 revolution.
Britain's foreign secretary, William Hague, is also due to meet his Iranian counterpart, Mohammad Javad Zarif, at the UN General Assembly meeting in New York.
The move has added to optimism that the Rouhani's election, who is a moderate, and his appointment of a largely pragmatic cabinet, has opened the door to a diplomatic solution to the 11-year international standoff over Iran's nuclear programme, the Guardian reports.
Tehran took the Foreign Office by surprise, tweeting on Rouhani's English-language feed that the president would also be prepared to meet Hague.
Diplomats said that the tweet reflected the new Iranian government's eagerness to make diplomatic headway on the nuclear issue.
According to the report, a Hague meeting with either Rouhani or Zarif could clear the way to restoring full diplomatic ties.
In a television interview aired on Sunday, Obama made clear that there was a diplomatic opening with Iran, not only over the nuclear question, but also over Syria.
He confirmed earlier reports that he and Rouhani had 'reached out' to each other, exchanging letters.
