"There has been no breakthrough today," said British Foreign Secretary William Hague after meetings with Kerry and the foreign ministers of France, Germany and Iran.
The trip gave Kerry a chance to ease an espionage dispute with Germany. After meeting with German Foreign Minister Frank-Walter Steinmeier, both stressed the importance of their cooperation in solving global crises, yet offered little indication they have fully mended ties.
"We're working, we're working, we just got here," said Kerry, chiding reporters asking about progress as today's meetings wound down.
But the dispute over Iran's enrichment program appeared to be defying the Western foreign ministers' combined diplomatic muscle.
Also Read
Tehran says it needs to expand enrichment to make reactor fuel but the US fears Tehran could steer the activity toward manufacturing the core of nuclear missiles.
The US wants deep enrichment cuts; Iran wants to greatly expand enrichment.
Steinmeier and French Foreign Minister Laurent Fabius left today, a few hours after they arrived.
Kerry und Hague stayed on for another day of diplomacy. Still, the dispute and other differences strongly indicated that six world powers and Tehran will need to continue negotiations until July 20 and could decide to extend their talks past that informal deadline for a deal.
Such an agreement would buy time to negotiate a pact limiting the scope of such programs in exchange for a full end to nuclear-related sanctions against Tehran.