BlackRock Chairman and CEO Larry Fink told CNBC on Thursday that China's relationship with North Korea is the worst it has ever been.

Fink, speaking ahead of President Donald Trump's meeting with Chinese President Xi Jinping in Florida, said China is slowly changing its behavior with North Korea.

"I think obviously North Korea will be a major component of the conversations, but let's be clear: China's relationship with North Korea at this moment is the worst it's ever been," Fink said on "Squawk Box."

The president, who previously declared China the "grand champion" of currency manipulation, is expected to discuss a range of issues with the Chinese president, including trade, North Korea and territorial disputes in the South China Sea.

Last week, Trump predicted a "difficult" meeting in a tweet.

@realDonaldTrump The meeting next week with China will be a very difficult one in that we can no longer have massive trade deficits...

Fink said Thursday he believes that the Chinese government is going to be a good listener.

"I actually am optimistic about this going on to be a good meeting," Fink said. "Both sides, actually need some form of success. I think they're going to find ways to improve the relationship."

Read more from Fink's interview: