France, Britain and Germany have expressed "serious doubts" about Iran's intentions to revive a nuclear deal in comments that were rejected by Tehran and called "very untimely" by Moscow.
Iran earlier this month sent its latest response to the EU's proposed text to restore the 2015 agreement under which Tehran had curtailed its nuclear programme in exchange for relief from US, EU and UN economic sanctions.
Diplomats have said Iran's response to the EU co-ordinator, seeking to link a revival of the deal with the closure of investigations by the International Atomic Energy Agency into uranium traces at three undeclared sites, was a step backwards.
France, Britain and Germany, the three European parties to the Joint Comprehensive Plan of Action, as the deal is formally known, vented their frustration about the issue on Saturday. This comes as IAEA's board of governors prepares to meet on Monday, three months after the European parties adopted a resolution urging Iran to provide credible answers on the issue.
"This latest demand raises serious doubts as to Iran's intentions and commitment to a successful outcome on the JCPOA," the three countries, known as the E3, said in a statement.
"Iran's position contradicts its legally binding obligations and jeopardises prospects of restoring the JCPOA."
Iran's Foreign Ministry spokesman Nasser Kanaani said the statement was "unconstructive".
"The three European countries are advised to play a more active role in providing solutions to end the few disagreements that remain", state media reported him as saying.
"If such an approach persists, they should also take responsibility for its consequences."
The European statement also prompted Russia's envoy to the talks to respond on Twitter, calling it "very untimely indeed". He dismissed the issue as something that "was not a serious obstacle".
Highlighting how entrenched positions are before next week, France's negotiator, Philippe Errera, called out his Russian counterpart.
"There is no longer an active negotiation, since Iran's last response — which you, unlike almost all your followers, have had access to," he said on Twitter.
Mr Ulyanov retorted that at least they agreed there was no active negotiation.
The US president at the time, Donald Trump, abandoned the deal in 2018 and reimposed US sanctions. This prompted Iran to start breaching the deal's nuclear curbs and reviving US, Arab and Israeli fears it may be seeking an atomic bomb. Iran denies seeking nuclear weapons.
The IAEA said on Wednesday that Iran's stock of uranium enriched to up to 60 per cent — close to weapons-grade — had grown to enough, if enriched further, for a nuclear bomb. It added that Tehran had still failed to explain the origin of the uranium particles.
"Given Iran’s failure to conclude the deal on the table, we will consult, alongside international partners, on how best to address Iran’s continued nuclear escalation and lack of co-operation with the IAEA regarding its NPT [Non-Proliferation Treaty] safeguards agreement," the E3 said.
It is unknown at this stage how the Western powers will respond, although diplomats said a new resolution at the IAEA was unlikely.
— With reporting from Reuters.
