Facebook CEO Mark Zuckerberg is talking tough, threatening now to unfriend Elizabeth Warren from Facebook if she keeps talking about breaking about companies like his as president.

“She’s already muted,” Zuckerberg told the Hamster. “If she becomes president and pushes this forward, she’s just unfriended. I’m sorry to say it.”

Warren in response subtweeted Zuckerberg saying “life is too short for fake friends.”