Negotiators for Iran and the UN's International Atomic Energy Agency refused to go into details. But their expressions of optimism and agreement not only to meet again but also to do that in Tehran all pointed toward forward movement.
Their decision to issue a joint statement, instead of their usual practice of speaking to reporters separately, also was seen as a sign of progress.
Comments from him and Iranian chief negotiator Reza Najafi, speaking in their own capacity, were even more bullish. Najafi spoke of a "new chapter of cooperation," with the IAEA, while Varjoranta said he expected to "complete our work as quickly as possible."
It was the second time this month that talks focused on international concerns over Iran's nuclear ambitions ended positively and in line with the stated determination of top officials within Iran's new government to work on reducing such fears.
Also Read
Both sides described their last round of these talks in October as positive, with Tehran ready to discuss some curbs on programs that can create both atomic energy and the fissile core of nuclear arms.
While the Vienna and Geneva talks are formally separate, they are linked by concerns over Iran's nuclear aspirations, and progress in one may result in advances in the other. Tehran denies either wanting or working on atomic arms.
Expectations of progress were raised even before Monday's opening Vienna round after Iranian Deputy Foreign Minister Abbas Araghchi met with IAEA chief Yukiya Amano and promised "new approaches" meant to end the impasse.