Iran warned European powers on Monday that it will further reduce its compliance with its 2015 nuclear deal in about a month’s time if they continue to fail to protect it from crippling US sanctions. European signatories to the deal have so far been helpless to prevent US President Donald Trump trying to force Iran to accept stricter limits to its nuclear activity and regional behavior by strangling its vital oil trade. Washington withdrew from the deal in May last year and reimposed sanctions against Tehran. Iran has threatened to block all energy exports out of the Strait of Hormuz, through which a fifth of global oil traffic passes, if it is unable to sell oil as promised by the accord in exchange for curbing its uranium enrichment program. “With the continuation of the inaction of the Europeans in carrying out their commitments (to the nuclear deal) ... Iran will take a third step (in reducing commitments) in approximately one month,” said Behrouz Kamalvandi, spokesman for the Atomic Energy Organization of Iran. Iran had increased its stockpile of heavy water above 130 tons and its reserve of enriched uranium above 300 kilograms, Kamalvandi told IRIB news agency. The deal - designed to forestall Iran making high-enriched uranium suitable for nuclear bombs in short order - permitted a maximum reserve of 300 kilograms of low-enriched uranium. It also set a cap of 130 tons of heavy water, which in large quantities can yield plutonium, an alternative atom bomb fuel. “What is certain is that by putting aside or suspending our commitments we will increase the speed of our nuclear activities,” said Kamalvandi. He did not specify what Iran’s next step would be, but Tehran warned last month it could reactivate centrifuge machines and ramp up enrichment of uranium to 20% fissile purity. The deal set an enrichment ceiling of 3.67%, the level deemed as appropriate for electricity generation and far below the 90% of weapons grade, though 20% would mark a big advance significantly reducing the time needed to yield bomb material. It has long denied seeking a nuclear bomb but appears to be cranking up enrichment levels gradually as leverage to push the nuclear deal’s remaining parties to do more to save it. All Iran’s steps, he said, were reversible if Britain, France, Germany, Russia and China eventually brought it protection from Washington’s sanctions squeeze.