European Union foreign ministers will hold an emergency meeting on Friday in Brussels to discuss ways to try to save the Iran nuclear deal, two diplomats said.
A third diplomat said the meeting would start at 1400 CET. Officially, the agenda has yet to be agreed, but one of the envoys said EU ministers would consider their response to Iran's decision to abandon limitations on enriching uranium.
Iran announced on Sunday that it would lift limitations on uranium enrichment, taking a further step back from commitments to a 2015 nuclear deal with Britain, France, Germany, Russia and China. Tehran said it would continue to cooperate with the U.N. nuclear watchdog.
Its decision followed a U.S. drone strike last week that killed Qassem Soleimani, one of Iran's top military commanders.
"We must be ready to react to Iran's breaches of the nuclear deal," one of the EU diplomats said. Asked if this could mean triggering a mechanism that moves closer towards reimposing international sanctions on Tehran, the envoy said: "It is increasingly likely, but not yet decided. Friday will be key."
Iran says its violations have been driven by the United States' withdrawal from the deal in 2018 and its reimposition of sanctions that have strangled Tehran's oil exports.
Iran has previously said it would return to compliance if Washington did so.