European signatories to a nuclear pact with Iran regretted on Tuesday Tehran’s decision to amass more low-enriched uranium than is permitted under the deal.
"We regret this decision by Iran, which calls into question an essential instrument of nuclear non-proliferation," the foreign ministers of Germany, France and Britain said in a joint statement with the EU's High Representative on Iran.
"We urge Iran to reverse this step and to refrain from further measures that undermine the nuclear deal," they said.
They added that they "are urgently considering next steps" under the terms of the agreement in close coordination with other signatories.
Tehran’s announcement that it has breached the low-enriched uranium stockpile limit prompted US President Donald Trump to say Iran was "playing with fire".
Earlier, France warned Iran against carrying out any further measures that could violate the nuclear deal, but appeared to hold off on confronting it over its decision to exceed its low-enriched uranium limits.
In a statement, President Emmanuel Macron said he had "noted with concern" Tehran's overstepping of the limit and called on it "to immediately reverse this overshoot and abstain from any other measure that would undermine its nuclear obligations".
He said he would continue in the coming days to work towards a resolution of the standoff between Iran and the US that would see Tehran "fully respect its obligations and continue to benefit from the economic advantages of the (2015) deal."
Tensions between Washington and Tehran have increased since Trump pulled Washington out of the pact last year and moved to bar all international sales of Iranian oil. Washington also blames Iran for attacks on oil tankers in the Gulf, something Tehran denies.
The European signatories to the accord have sought to pull back the two longstanding foes from direct confrontation, fearing a mistake could lead to war accidentally.
Israel has encouraged the Trump administration to press ahead with sanctions against Iran, predicting that Tehran will eventually renegotiate a more limiting nuclear deal.
But Foreign Minister Israel Katz told an international security forum that Iran might accidentally stumble out of what he termed the "gray zone" of contained confrontation.
"It should be taken into account that mistaken calculations by the (Iranian) regime ... are liable to bring about a shift from the 'gray zone' to the 'red zone' - that is, a military conflagration," he said in a speech to the Herzliya Conference.
"We must be prepared for this, and thus the State of Israel continues to devote itself to building up its military might for the event that it will have to respond to escalation scenarios."
