After a report Friday that Iran is willing to work on the basis of earlier nuclear talks Tehran media insisted there has been no change in negotiating posture.

A source quoted by Reuters said that Iran was willing to continue the Vienna talks on the basis of texts prepared in June and added that world powers would test in the next couple of days whether this was true.

Iran's Tasnim news agency affiliated with the Revolutionary Guard said Iran has not changed its negotiating position.

The official government news website IRNA also reiterated that diplomats in Vienna are reviewing Iran's new proposals.

Working groups to discuss sanctions and the nuclear aspects of reviving a 2015 deal will begin on Friday.

The first six rounds of nuclear talks in Vienna drafted texts that the new Iranian government did not recognize as an a basis of new talks. It argued for everything to be renegotiated, demanding that all post-2018 US sanctions be removed at once before it would return to compliance with the 2015 nuclear deal, JCPOA.

The United States and its European allies were dismayed by Iran’s new demands and have warned that time is running out for progress in the talks.

"Iran said it accepted to work from the June texts. This will now be put to the test over the next couple of days," the source said, speaking on condition of anonymity.