The 40-year-old television personality discussed the 38-year-old rapper's recent comments about Taylor Swift and his "Saturday Night Live" meltdown in an interview with "ET Canada."
"I've always thought he's a maniac and [now] he just sounds like more of one. He's delusional," Handler said.
"He's acted like this for years and now people are surprised he's acting like this? He did this to Taylor Swift five or six years ago."
West claimed he "made" Swift famous by interrupting her 2009 MTV Video Music Awards acceptance speech in his new song, "Famous," which debuted Feb. 11.
The rapper again mentioned Swift in a lengthy rant prior to his "Saturday Night Live" performance days later.
"Why is it surprising? He's acted like this for years," Handler added.
"He's not stable and he's delusional. And now he'll have a mental breakdown in front of everybody even though he's been in this state for years."
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West was recorded ranting about changes to the "SNL" stage and his own influence prior to the NBC sketch comedy's Feb. 13 episode.
The rapper declared himself "50 percent more influential" than Stanley Kubrick, Pablo Picasso and Paul the Apostle in his meltdown.
"A wise man should be humble enough to admit when he's wrong and change his mind based on new information," West tweeted last week while reflecting on how he said he'll "take the rap throne." "My number one enemy had been my ego... there is only one throne and that's God's."
Handler hosted E! series "The Chelsea Handler Show" before starring on seven seasons of Chelsea Lately, and appeared in four-part Netflix documentary "Chelsea Does" in January. She is developing another series with the streaming site for 2016.
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