President Donald Trump warned Thursday of the possibility of “massive conflict” in the Middle East that could take place “soon.”

US officials are increasingly concerned that the risk of Israel striking Iran has risen after Tehran said on Thursday that it would ramp up its nuclear activities due to the International Atomic Energy Agency passing a resolution saying that the country was not in compliance with its non-proliferation commitments, senior US officials told CNN.

Questioned about a potential strike on Thursday, Trump said it “could very well happen.”

“I don’t want to say imminent, but it’s something that could very well happen,” Trump told reporters at the White House.

US embassies in the Middle East carried out emergency action assessments this week, and that process is ongoing as the US monitors the threat environment in the region, the officials said.

Asked what the Israelis told him to prompt the departure of US personnel from the region, Trump replied: “They didn’t tell me anything, but I said look, there’s a chance of massive conflict.”

He described the deliberations that led him to the decision.

“We have a lot of American people in this area, and I said, look, we gotta tell them to get out cause something could happen – soon. And I don’t want to be the one that didn’t give any warning and missiles are flying into their buildings. It’s possible. So I had to do it. You know, I had the choice – do I do it or not? Doing it has its downside but it also has its upside, like you’re going to save a lot of lives if it should happen. Hopefully that doesn’t happen.”

Trump also said he does not want Israel to target Iran as negotiations on a potential nuclear deal continue, with a sixth round of talks set for Sunday in Oman.

“I want to have an agreement with Iran. We’re fairly close to an agreement. … As long as I think there is an agreement, I don’t want them going in because that would blow it. Might help it, actually, but also could blow it,” he said when asked about a potential Israeli strike.