Iran has broken through the international limit on its stockpile of uranium in the 2015 nuclear deal and is poised to dramatically ramp up enrichment, officials in Tehran said Monday as they blamed President Trump for kick-starting a crisis and put the burden on the U.S. and Europe to find a way out.

Iranian Foreign Minister Mohammad Javad Zarif told reporters that Iran intentionally exceeded the uranium limits laid out in a 2015 multinational deal — which the Trump administration repudiated last year — that placed firm restrictions on its nuclear program. International nuclear watchdogs quickly confirmed that Iran had exceeded the cap, which allows the nation to have no more than about 661 pounds of uranium enriched to a maximum of 3.67%, effectively extending the time needed to develop a nuclear bomb.

U.S. officials said they would not back off on the harsh pressure campaign on Tehran, and Mr. Trump told reporters in the Oval Office that Iranian officials were “playing with fire.”

While the announcement doesn’t mean that Iran immediately has the material needed for a nuclear weapon — analysts still estimate that it would take Tehran about a year to make a nuclear bomb — it highlights the increasingly aggressive response to reimposed U.S. economic sanctions and continued threats of military force. On the heels of Iran’s alleged oil tanker bombings in the Gulf of Oman and downing of an American drone, some analysts say Iran’s declaration is further proof that Iran has settled on a provocative strategy to pressure Washington and its allies back to the negotiating table — or put the blame on Washington if conflict breaks out.

European leaders pleaded for diplomacy and urged Iran to reverse course, but Mr. Zarif blamed Washington for forcing Tehran’s hand. He said Mr. Trump’s withdrawal of the U.S. from the Obama-era nuclear deal meant Iran was free to begin disregarding several of its key provisions. Without a resolution, he said, Tehran is prepared to go much further.

“We had previously announced this, and we have said it transparently what we are going to do,” Mr. Zarif said. “We are going to act according to what we have announced, and we consider it our right reserved in the nuclear deal.

“The next step is about the 3.67% limitation, which we will implement too,” he added, referring to a key figure laid out in the 2015 pact that allows Iran to enrich uranium for peaceful nuclear power but keeps it well below the higher levels needed to produce weapons.

But Mr. Zarif also argued that Iran technically had not violated the 2015 agreement, saying Tehran was within its rights to react when another party — the U.S. — abrogated its obligations under the accord.

Soon after Mr. Zarif’s comments, officials with the International Atomic Energy Agency confirmed that Iran had broken the threshold, though the watchdog didn’t give a specific figure on the nation’s uranium stockpiles.

The reaction from Washington was harsh, and administration officials suggested that they will continue pressuring Iran until the country stops all uranium enrichment — a step that appears unlikely given Tehran’s recent moves.

“It was a mistake under the Iran nuclear deal to allow Iran to enrich uranium at any level,” White House press secretary Stephanie Grisham said in a statement. “There is little doubt that even before the deal’s existence, Iran was violating its terms. We must restore the longstanding nonproliferation standard of no enrichment for Iran. The United States and its allies will never allow Iran to develop nuclear weapons.

“Maximum pressure on the Iranian regime will continue until its leaders alter their course of action,” she continued. “The regime must end its nuclear ambitions and its malign behavior.”

The White House statement contradicted U.N. watchdog findings that Iran had largely abided by the 2015 nuclear limits until the most recent action. The U.S., Britain, France, Germany, Russia and China are all signatories to the agreement, and all but the U.S. still support it.

In his own statement, Secretary of State Mike Pompeo said the announcement is an example of how Iran uses its nuclear ambitions for leverage.

“The world’s leading state sponsor of terrorism continues to use its nuclear program to extort the international community and threaten regional security,” the top U.S. diplomat said.

Still, the news wasn’t a surprise. Iran for months had threatened to begin disregarding the terms of the nuclear agreement, citing the U.S.-led campaign to squeeze its economy and shut off its crucial oil export markets.

Iran’s moves now put even more pressure on the leading European powers. Britain, Germany and France have stood by the nuclear deal even as the U.S. exited and so far have resisted the White House’s call to reimpose their own set of economic sanctions.

European leaders struck a cautious note Monday and urged Iran to not go any further.

“Deeply worried by Iran’s announcement that it has broken existing nuclear deal obligations. UK remains committed to making deal work & using all diplomatic tools to deescalate regional tensions,” British Foreign Secretary Jeremy Hunt said in a Twitter message.

European Union spokeswoman Maja Kocijancic said the EU “remains fully committed to the agreement as long as Iran continues to fully implement its nuclear commitments.”

Mr. Zarif said Iran is not walking away from the deal entirely. In a series of tweets, he pointed to specific language in the 2015 deal that allows Iran to break some of its terms if other signatories first violate the accord. He said that line was crossed when the U.S. left the pact last year.

The position received support from Russian Deputy Foreign Minister Sergei Ryabkov, who noted Monday that Iran had warned it would take action and that it was a “natural result” of Mr. Trump’s maximum pressure campaign. He said Iran was reacting to American sanctions, which represent an attempt to “strangle” the Islamic republic.

Some of Mr. Trump’s American critics also say that his decision to exit the agreement sparked the crisis.

“When you’re in a hole, the best advice is to stop digging,” said Jamal Abdi, president of the National Iranian American Council. “Returning the U.S. to compliance with the nuclear deal would be the best way to reverse the damage of Trump’s withdrawal. At minimum, Trump should suspend the ‘maximum pressure’ sanctions in exchange for Iran suspending recent breaches of the nuclear deal and to allow space for negotiations.”

But many Republicans are pushing the president to respond by cracking down on Tehran even harder and to go beyond the already unprecedented set of economic sanctions and global embargo on Iranian oil that the administration imposed earlier this year.

“The catastrophic Obama Iran nuclear deal was built to allow Iran to cheat, both by making it difficult to detect violations and by giving other countries an incentive to dismiss those violations when they became undeniable,” Sen. Ted Cruz, Texas Republican, said in a statement. “It’s time to put an end to this charade. The Trump administration should increase sanctions on Iran’s nuclear program … and I will continue to work with my congressional colleagues to ensure that maximum pressure means maximum pressure.”

⦁ This article is based in part on wire service reports.