The so-called "E3" governments said Iran was moving "well beyond" limits set down in the Joint Comprehensive Plan of Action (JCPoA), a 2015 deal designed to curb its nuclear ambitions.

Iran has now "taken further significant steps in hollowing out the JCPoA", the European governments said in a joint statement.

By enriching uranium up to 60 percent at its Fordo plant, Iran was challenging global non-proliferation, they said.

"This step, which carries significant proliferation-related risks, has no credible civilian justification," the E3 countries said.

"We will continue to consult, alongside international partners, on how best to address Iran's continued nuclear escalation."