Signatories of the Iran nuclear deal are meeting in Vienna on Friday in a bid to save the agreement, as Iran warned the deal had been put "in intensive care" by Washington's dramatic withdrawal earlier this month.
For the first time since the accord came into force in 2015, China, Russia, France, Britain and Germany will gather -- at Iran's request -- without the United States, which pulled out on May 8.
US President Donald Trump has long trashed the deal with Iran -- concluded under his predecessor Barack Obama -- saying it did not do enough to curtail Tehran's nuclear ambitions.
He also said it did not go far enough in restricting Iran's ballistic missile programme, or its intervention in regional conflicts from Yemen to Iraq and Syria.
A senior Iranian official rejected any attempt to link the deal, known as Joint Comprehensive Plan of Action (JCPOA) to other such issues, saying it would mean "we lose JCPOA and we (would) make the other issues even more complicated to resolve", adding that it was pointless for the Europeans to try to "appease" Trump.
"We have now a deal which is in the intensive care unit, it's dying," he said.
He added that the Europeans had promised Iran an "economic package" to maintain the benefits of the JCPOA for Iran despite the reintroduction of US sanctions.
Iran expected this package by the end of May, he said, adding that Iran had only "a few weeks" before having to decide whether to keep participating in the deal or not.
Since the US pull out, the other signatories have embarked on a diplomatic marathon to try to keep the agreement afloat.
According to a report seen by AFP Thursday, an International Atomic Energy Agency believes Iran is still abiding by the deal's key restrictions on its nuclear facilities in return for relief from damaging economic sanctions.
The IAEA, however, is "encouraging (Iran) to go above and beyond the requirements" of the deal in order to boost confidence, said a senior diplomat in Vienna, where the IAEA is based.
Iran has threatened to restart its uranium enrichment programme at an "industrial level" if the deal falls apart.
The five signatories still committed to the agreement have said they want Iran to stay in the deal, with the European countries saying they would not rule out further talks with the Islamic Republic on an expanded text.
However, several Iranian officials warned that the Vienna meeting would be devoted to the existing agreement only, implying that there was no question of broadening the discussions.