Iran breaches limit on enrichment in 2015 pact

TEHRAN — Iran on Monday began enriching uranium to 4.5%, breaking the limit set by its nuclear deal with world powers, while it is still seeking a way for Europe to help it bypass U.S. sanctions amid heightened tensions between Tehran and Washington.

The move shows that the Islamic Republic is trying to increase pressure on those still in the 2015 nuclear deal. It also comes just days after Iran acknowledged breaking the 300-kilogram (661-pound) limit on its low-enriched uranium stockpile, another term of the accord.

The International Atomic Energy Agency, the U.N.’s nuclear watchdog, confirmed that Iran surpassed the enrichment threshold.

Experts warn that higher enrichment and a growing stockpile could begin to reduce the one-year window Iran would need to have enough material for an atomic weapon, something Iran denies it wants but the deal prevented. While the steps now taken by Iran remain quickly reversible, Europe so far has struggled to respond.

There are fears that a miscalculation in the crisis could explode into open conflict. President Trump, who withdrew the U.S. from the nuclear deal over a year ago and re-imposed crippling economic sanctions on Iran, nearly bombed the country last month after Tehran shot down a U.S. military surveillance drone. Even China, engaged in delicate trade negotiations with the White House, on Monday openly criticized America’s policy toward Iran.

“What I want to emphasize is that the maximum pressure the U.S. imposes on Iran is the root cause of the crisis in the Iranian nuclear issue,” said Geng Shuang, a Chinese Foreign Ministry spokesman. “It has been proven that unilateral bullying has become a worsening tumor and is creating more problems and greater crises on a global scale.”

Under the deal, Iran has been closely monitored by inspectors from the IAEA,...