Iran on Monday held an event commemorating the 40th anniversary of the 1979 hostage crisis at the U.S. Embassy and also announced fresh violations of the 2015 nuclear deal it arranged with former U.S. President Barack Obama, including plans to deploy a new uranium centrifuge that would work 50 times faster than the equipment it was permitted to use under the deal.

Ali Akbar Salehi, head of the Iranian Atomic Energy Organization, announced the prototype centrifuge, adding Tehran is now spinning 60 centrifuges of less advanced design — twice as many as the nuclear deal allowed.

Fox News reported Iran is getting close to a one-year “breakout” period to producing enough weapons-grade material to build an atomic bomb, a significant threshold because only the most drastic measures could prevent the Iranians from taking the final steps at that point.

“In the four years since agreeing to the nuke deal, which was brokered by the Obama administration, Iran has already flaunted its disregard of stockpile and enrichment limitations, all the while hinting to European countries that increased economic aid and additional sanctions relief could persuade leaders to agree to a new deal or come back into compliance with the current one,” Fox News noted.

Salehi teased additional nuclear deal violations to illustrate Iran’s “capacity and determination.” The European Union responded on Monday by warning that while it remains “committed” to the nuclear deal, its commitment may weaken if the Iranians persist in escalating their violations.

“We have continued to urge Iran to reverse such steps without delay and to refrain from other measures that would undermine the nuclear deal,” said Maja Kocijancic, a spokeswoman for top E.U. diplomat Federica Mogherini.

Germany, which has been strongly supportive of the deal, on Monday called Iran’s latest moves “unacceptable” and warned that Tehran is “doing nothing less than putting the entire nuclear agreement at risk.”

The International Atomic Energy Agency (IAEA), the United Nations nuclear watchdog agency, did not immediately comment on Iran’s latest provocations.

Iranian state media on Monday reported over a thousand government-sponsored rallies to commemorate the takeover of the U.S. embassy 40 years ago. Participants in the rallies chanted “Death to America” and “Death to Israel,” while Iranian officials instructed them to see the hostage crisis as a demonstration of defiance against Western “bullying.”

“Those who believe that negotiations with the enemy will solve our problems are 100 percent wrong,” Supreme Leader Ayatollah Ali Khamenei declared on Sunday, renewing his ban against negotiations with the United States.

The White House responded with a statement on Monday honoring the American victims of the “brazen act” of terrorism committed by Iran in 1979.

“The Iranian regime continues to target innocent civilians for use as pawns in its failed foreign relations. Until Iran changes this and its other hostile behavior, we will continue to impose crippling sanctions,” the White House said.

The U.S. statement said Iran’s leaders have a choice to make: “Instead of being the world’s leading state sponsor of terrorism, it can put the Iranian people first. It can choose peace over hostage taking, assassinations, sabotage, maritime hijacking, and attacks on global oil markets. The United States seeks peace, and we support the Iranian people. It is time for the Iranian regime to do the same.”