We're hearing more now from UK Foreign Secretary David Lammy, who has been involved in talks today in Geneva.
Lammy says he was there with his European counterparts discussing "our absolute firmness" that Iran "cannot have nuclear capability that would endanger the immediate Middle East but also the global community".
"We had constructive discussions today and we will continue", he says.
He adds that the delegation also "urged" the Iranians to "get back into discussions" with the US - referring to talks between Iran and the US on Iran's nuclear programme.
Lammy says that in today's discussions, he and the European foreign ministers were "very clear" that "zero enrichment" of uranium is the "starting point".
