Mic drop. Kanye West was at it again while at 1 Oak in L.A. on Tuesday, February 23. A source tells Us Weekly that the rapper ranted about his ex-girlfriend Amber Rose and pop superstar Taylor Swift while standing in the DJ booth.

West, 38, didn't hold back. The rapper called out Swift, 26, first, and claimed again that she was aware of the controversial lyrics about her in his song "Famous." In the track, which is from his new album, The Life of Pablo, West calls Swift a "bitch" and says he made her famous. In response, Swift subtly bashed West's comments while accepting the Album of the Year accolade at the Grammy Awards earlier this month.

"I called Taylor. I played her [it]. I told her, look, I said, 'Taylor, I talked to my wife [Kim Kardashian] about it. And I said, 'How you feel about this line?' I was like, Taylor, 'I think you and me still might have sex,'" West claimed on Tuesday.

"She said, 'Oh, Kanye, I like that line.' Then she won and went and said something completely different. She not cool no more, she had two seconds to be cool and she f--ked it up," he continued. "Make her stop trying to make up stories." (West also tweeted on February 12 that Swift "came up with" the lyric.)

West's feud with Swift has escalated since he debuted "Famous" during his Yeezy Season 3 New York Fashion Week event on February 11. Two days after the show — one day before the Grammys — the rapper called Swift a "fake ass" backstage at Saturday Night Live, where he was the week's special guest.

The fashion designer also had a war of words with Rose, 29, last month. Rose, who dated West from 2010 to 2012, bashed the rapper after he tweeted that he "owns" her and Wiz Khalifa's 2-year-old son, Sebastian.

"Awww @kanyewest are u mad I'm not around to play in ur a--hole anymore? #FingersInTheBootyAssBitch," she tweeted on January 27. "Lol @kanyewest Now u wanna delete ur tweets cuz Muva has arrived? #TwitterFingers #UrGettingBodiedByAStripperN---a."

As previously reported, West initially went after Khalifa, 28, because he mistakenly thought that Khalifa dissed Kardashian, 35. Rose later made nice and took a selfie with Kardashian at Kris Jenner's Calabasas, California, home. Click here to see the pic. 

"My wife got Amber back to make an apology," West claimed at 1 Oak. "Amber never stick no fingers in my ass. I don't play like that!"

West had family on hand during his rant on Tuesday night. The source says that he walked in with Pusha T and was later joined by his sister-in-law Kourtney Kardashian, her BFF Brittny Gastineau and Scott Disick.

"[Kourtney and Scott] were super friendly and sitting close all night," the eyewitness says. "Certainly not looking like exes."

Kim, meanwhile, was not in attendance, but it's unknown why. An insider reveals in the new issue of Us Weekly that Kim "demanded" West to seek professional help amid his tantrums. He's yet to agree.

For more on Kimye, pick up the new issue of Us Weekly, on stands now.

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