Bill O'Reilly: 'Check in with me around 2023' for apology to Putin

After Bill O'Reilly called Russian President Vladimir Putin "a killer" during his interview with U.S. President Donald Trump, the Kremlin demanded that the Fox News host apologize — something that O'Reilly says he's "working on."

O'Reilly's sit-down with Trump, which aired Sunday on the Super Bowl pre-game show, covered a wide variety of topics, including the new president's relationship with the Russian leader. O'Reilly grilled Trump on the relationship, at one point saying, "He's a killer, though. Putin's a killer."

The Russian government took issue with that characterization; on Monday, Kremlin spokesman Dmitri S. Peskov called the comments "unacceptable" and "insulting" and stated that they would like an apology.

O'Reilly addressed the request on Monday night's edition of The O'Reilly Factor, this time calling Putin "a tyrant."

"Apparently, the Putin administration in Moscow is demanding that I, your humble correspondent, apologize for saying old Vlad is a killer," he said. "So I'm working on that apology, but it may take a little time. Might want to check in with me around 2023."

He then concluded by recommending reading Bill Gertz' book IWar: War and Peace in the Information Age "to learn more about the violent history of Vladimir Putin." <script type="text/javascript" src="http://video.foxnews.com/v/embed.js?id=5313200375001&amp;w=466&amp;h=263"></script><noscript>Watch the latest video at <a href="http://video.foxnews.com">video.foxnews.com</a></noscript>íÞ÷ÛƼçÍÛë9ã¾<éÝtÛoysÝ]÷†½ÝîÞ

See video from Monday night's segment above.