<p>An "accident" took place at an Iranian nuclear facility on Sunday but caused no casualties or damage, the Fars news agency reported, citing the spokesman of Iran's nuclear agency.</p>.<p>Behrouz Kamalvandi said there had been "an accident in part of the electrical circuit of the (uranium) enrichment facility" at the Natanz complex, a day after Iran announced it had started up advanced uranium enrichment centrifuges at the site in a breach of its undertakings under a troubled 2015 nuclear deal.</p>.<p>There were "no casualties nor pollution", he said, adding that "the causes of the accident are under investigation and more details will be released later".</p>.<p>The accident follows an explosion at a factory for advanced centrifuges at Natanz last July.</p>.<p>The authorities blamed that incident on "sabotage" by "terrorists", but have not released the results of their investigation into it.</p>.<p>President Hassan Rouhani on Sunday inaugurated a replacement factory at Natanz as well as a cascade of centrifuges for enriching uranium and two test cascades, in a ceremony broadcast by state television.</p>.<p>The new equipment enables Iran to enrich uranium more quickly and in higher quantities, to levels that violate the 2015 nuclear deal.</p>.<p>The administration of then-US president Donald Trump withdrew from the multilateral accord in 2018 and re-imposed biting sanctions. Iran later responded by progressively rolling back its own commitments under the agreement.</p>.<p>Parties to the deal opened talks in Vienna on Tuesday with the aim of bringing the US back to the deal, bringing Iran back into compliance and lifting sanctions.</p>
<p>An "accident" took place at an Iranian nuclear facility on Sunday but caused no casualties or damage, the Fars news agency reported, citing the spokesman of Iran's nuclear agency.</p>.<p>Behrouz Kamalvandi said there had been "an accident in part of the electrical circuit of the (uranium) enrichment facility" at the Natanz complex, a day after Iran announced it had started up advanced uranium enrichment centrifuges at the site in a breach of its undertakings under a troubled 2015 nuclear deal.</p>.<p>There were "no casualties nor pollution", he said, adding that "the causes of the accident are under investigation and more details will be released later".</p>.<p>The accident follows an explosion at a factory for advanced centrifuges at Natanz last July.</p>.<p>The authorities blamed that incident on "sabotage" by "terrorists", but have not released the results of their investigation into it.</p>.<p>President Hassan Rouhani on Sunday inaugurated a replacement factory at Natanz as well as a cascade of centrifuges for enriching uranium and two test cascades, in a ceremony broadcast by state television.</p>.<p>The new equipment enables Iran to enrich uranium more quickly and in higher quantities, to levels that violate the 2015 nuclear deal.</p>.<p>The administration of then-US president Donald Trump withdrew from the multilateral accord in 2018 and re-imposed biting sanctions. Iran later responded by progressively rolling back its own commitments under the agreement.</p>.<p>Parties to the deal opened talks in Vienna on Tuesday with the aim of bringing the US back to the deal, bringing Iran back into compliance and lifting sanctions.</p>