The senior European official chairing Iran nuclear talks in Vienna tweeted Wednesday he was heading to the Austrian capital to resume discussions.

“On my way to Vienna to discuss JCPOA back to full implementation on the basis of the coordinator’s text tabled on 20 July,” Enrique Mora tweeted. Axios website cited a US official confirming the US and Iran would “resume indirect talks” Thursday.

The European foreign policy chief Joseph Borrell has circulated written proposals for concluding year-long Vienna talks between Iran and world powers, paused in March, aimed at restoring the 2015 Iran nuclear agreement, the JCPOA (Joint Comprehensive Plan of Action). Neither these talks, nor a bilateral round in Qatar in June, bridged differences between Iran and the United States.

Mora’s tweet did not explain whether resumed Vienna talks would involve all earlier participants – China, France, Germany, Russia, and the United Kingdom, as well as Iran and the US. All have ambassadors to United Nations bodies in Vienna who cover the International Atomic Energy Agency. In neither the Vienna nor Qatar negotiations did American and Iranian officials meet, with contacts mediated largely by European officials.

“We are headed back to Vienna with low expectations but are going to make a good faith effort,” the US official told Axios. President Joe Biden, who faces domestic criticism over his approach to Iran, has recently tightened sanctions, while Borrell in a Financial Times article July 26 suggested his new text offered “the best possible deal” and that “decisions need to be taken now.”