Iranian and U.N. negotiators say Tehran has presented "constructive" ideas at talks over a proposed probe of suspicions Tehran worked on nuclear arms and have set a next round for Nov. 11 in Tehran.
They refused to detail progress made. But their expressions of optimism, agreement to meet again and to do so in Iran indicated that the talks are gaining traction after nearly two years of deadlock.
The two sides usually speak separately after such meetings and a joint statement issued this time also indicated progress. It spoke of a "substantive discussion" and "cooperation" over two days, ending Tuesday.
Iranian negotiator Reza Najafi spoke of a "new chapter of cooperation" with negotiators from the U.N.'s International Atomic Energy Agency.
Iran denies working on — or interest in — nuclear arms.