Secretary of State Mike Pompeo claimed an “imminent threat” against American lives forced President Trump to make the decision to kill Iranian Gen. Qassem Soleimani.

Soleimani, who was responsible for the deaths of hundreds of American soldiers over the past two decades, was killed Thursday after weeks of counterstrikes following the death of an American contractor and an attack on the U.S. Embassy in Iraq.

During an interview about the strike on New Day, Pompeo was asked to explain why Trump decided to kill Soleimani at this moment when the Iranian general had been targeting and killing Americans for decades.

“What’s different today is that Iran has now been engaged for months in dozens and dozens of attacks throughout the region. President Trump has shown tremendous restraint to date. We’ve made clear to the Iranians that we were not going to tolerate the killing of Americans. On December 27th, an American was killed in Iraq. And then we watched the intelligence flow in that talked about Soleimani’s travels and the work he was doing to put Americans further at risk,” said Pompeo.

He added, “It was time to take action so that we can disrupt this plot, to deter further aggression from Qassem Soleimani and the Iranian regime. As well as to attempt to de-escalate the situation. The risk of doing nothing was enormous. Intelligence community made that assessment and President Trump acted decisively last night.”

Pompeo noted that Trump’s decision to kill Soleimani “saved American lives,” despite not being able to give further details about the exact plan he expected the Iranian general to execute against the United States.

[Read more: President Trump releases statement on death of Soleimani]