The EU has said it is studying Iran’s response to a draft agreement intended to save the 2015 nuclear accord as the bloc seeks to prevent the deal’s total collapse and to avert a new crisis.

The EU received Tehran’s response to the draft late on Monday. “We are studying it and are consulting with the other JCPOA [nuclear accord] participants and the US on the way ahead,” an EU spokesperson said. EU officials have described the draft, which was discussed by Iran and the US at indirect talks in Vienna this month, as the “final text”.

Analysts and diplomats said there were signs of some progress at the negotiations that are aimed at striking a deal under which the US agrees to rejoin the accord and lift many sanctions on Iran in return for Tehran drastically reducing its nuclear activity. But there were still outstanding issues after 16 months of EU-mediated talks that have often floundered as the main protagonists have blamed each other for deadlocks.