US-Iran Nuclear Talks Collapse After 21-Hour Marathon Session in Islamabad

"We have been at it now for 21 hours, and we've had a number of substantive discussions with the Iranians. That's the good news. The bad news is that we have not reached an agreement," Vance told reporters at a press conference in the early hours of Sunday morning .

The Vice President said US negotiators had clearly outlined their position but Tehran declined to accept the terms.

"We've made very clear what our red lines are, what things we're willing to accommodate them on, and what things we're not willing to accommodate them on, and we've made that as clear as we possibly could, and they have chosen not to accept our terms," he said .

Vance emphasised that the core US objective remained preventing Iran from acquiring nuclear weapons capability.

"The simple fact is that we need to see an affirmative commitment that they will not seek a nuclear weapon, and they will not seek the tools that would enable them to quickly achieve a nuclear weapon," he said .

He added that Washington was seeking long-term assurances from Tehran, not temporary commitments.

"Do we see a fundamental commitment of will for the Iranians not to develop a nuclear weapon, not just now, not just two years from now, but for the long term. We haven't seen that yet. We hope that we will," Vance said .

Despite the breakdown, the Vice President described the US approach as flexible and conducted in good faith under instructions from the President.

"I think that we were quite flexible. We were quite accommodating. The President told us, You need to come here in good faith and make your best effort to get a deal. We did that, and unfortunately, we weren't able to make making headway," he said .

Vance also underlined the extensive coordination with the US leadership during the negotiations.

"We were talking to the president consistently. I don't know how many times we talked to him, a half dozen times, a dozen times over the past 21 hours," he said, adding that officials remained in contact with the wider national security team throughout the talks .

He confirmed that Washington has put forward what it considers its final proposal.

"We leave here with a very simple proposal, a method of understanding that is Our final and best offer. We'll see," Vance said .

The failed talks mark a setback in efforts to revive diplomatic engagement over Iran's nuclear programme, which has long been a point of contention between Washington and Tehran. Previous negotiations have stalled over verification measures, sanctions relief and the scope of Iran's enrichment activities.

- IANS