“The Vienna talks have made significant progress over the past few weeks due to Iran’s initiatives and goodwill,” he said, adding that the agreement between Iran and the International Atomic Energy Agency to draw up a joint roadmap to resolve the remaining issues proves this.
The source noted that the US has delayed the process of reaching a good agreement by dragging its feet on making political decisions.
He said the US delegation in Vienna is waiting to receive necessary instructions on the remaining issues and that an agreement in Vienna today requires, more than anything else, a US response to proposals made in the talks.
Iran and the P4+1 group of countries started their eighth round of talks to revive the 2015 nuclear deal in December.
During this period, they also drew up a draft agreement meticulously and closed many gaps.
A couple of differences remain which Iran says their resolution depends on political decisions in the US. The chief Iranian negotiator Ali Bagheri is now back in Tehran for consultations and reports say will return to Vienna soon.