European Union foreign policy chief Kaja Kallas on Sunday urged all sides to step back and return to the negotiating table, after U.S. forces struck three Iranian nuclear sites.

“Iran must not be allowed to develop a nuclear weapon,” Kallas said in a post on the social media platform X.

Open gallery view European Union foreign policy chief Kaja Kallas. Credit: Mauro Scrobogna/AP

“I urge all sides to step back, return to the negotiating table and prevent further escalation,” she said, adding that EU foreign ministers will discuss the situation tomorrow.

U.S. President Donald Trump, accompanied by Vice President JD Vance, Secretary of State Marco Rubio and Secretary of Defense Pete Hegseth, confirmed that Iran’s key nuclear enrichment facilities have been “completely and totally obliterated,” in his address to the nation following the U.S. strikes on Iran.

Trump also thanked Israel’s Prime Minister Benjamin Netanyahu, saying that “they worked as a team.” He also thanked the Israeli military, and warned Iran: “There will be either peace or there will be tragedy for Iran, far greater than we have witnessed over the last eight days. Remember, there are many targets left.”

He continued, saying that “Tonight’s was the most difficult of them all, by far, and perhaps the most lethal, but if peace does not come quickly. We will go after those other targets with precision, speed and skill.”