Former CIA director John Brennan praised Sen. John McCain on Tuesday but acknowledged that the Senator used to berate him.

“Senator McCain was an exceptionally principled individual,” Brennan said in an interview with NBC News. “My last engagement with him, it was a very contentious one, where he hurled some profanities at me over some differences in policy.”

He said that McCain was furious with him while debating the proper response to the war in Syria. Brennan is now a paid contributor for NBC News.

“Even though it was quite heated, I had the greatest respect for Senator McCain because he was a principled individual,” Brennan said.

Brennan also praised Sen. Jeff Flake and Sen. Bob Corker for speaking out against Trump, signaling optimism that others would follow McCain’s lead after his death.

“I’d like to think that there are going to be senators now, who will be thinking about Senator McCain’s legacy and what he stood for, and who adopt some of the very same principled positions and speak truth to power,” he said.

Brennan declined an opportunity to criticize Trump, citing his preference to celebrate McCain’s life instead.