In case you forgot ... Nicki Minaj STILL HATES Mariah Carey ... and moments ago, she went after the diva AGAIN ... calling her a bitter old woman with no personality.

Minaj just unloaded on Twitter, following a series of heated exchanges on "American Idol" last night.  During the show, Mariah spit a little trash talk Nicki's way ... and taunted her for never having a #1 single on the Billboard Hot 100.


Nicki took some shots back at Mariah on the show -- at one point breaking out a cotton swab and telling Mariah to clean out her ears.

But moments ago, Nicki continued the war on Twitter ... telling critics to ask themselves "Why a woman SO successful at her age, is still so INSECURE, and bitter."

Minaj also made a reference to reports that "Idol" producers were recently looking to replace Mariah with former judge Jennifer Lopez:

"All dem #1s but JLo phone ringin? Lol. I guess having a personality, being a secure woman, and giving genuine critique still trumps that." So far, no response from Mariah.

Of course, Nicki and Mariah have been at each other's throats since before the season even began ... 'memba this video from last year?

President Barack Obama has a message for Nicki Minaj and Mariah Carey -- GIVE PEACE A CHANCE!!!!!

The war at the "American Idol" judges' table was escalated all the way to the Commander In Chief this weekend when POTUS appeared on Michael Yo's radio show.

"I think that they are going to be able to sort it out," Obama said ... "I am confident."

Obama continued, "I'm all about bringing people together, working for the same cause. I think both outstanding artists are going to be able to make sure that they're moving forward and not going backwards."

And when asked who's his favorite, Obama actually picked a side -- replying, "Mariah. She's actually done some events for us. I've gotten to know her and Nick [Cannon]. She's a wonderful lady."

He added ... "Nicki, I don't know, but I've got her on my iPod."

Jennifer Hudson knows a thing or two about "American Idol" ... which is why it's very interesting that she's calling total BS on the war between Mariah Carey vs. Nicki Minaj.

"I don't believe it," Hudson told us at LAX this weekend ... adding, "I think it's just for ratings for the show."

Hudson isn't just a former "Idol" finalist -- she's appeared on the show multiple times over the years ... and even performed on "A.I." back in April.

And Jennifer ain't the only superstar who thinks the judges' feud is fake -- "The Voice" star Cee Lo also thinks the fight could have been staged for publicity.

Nick Cannon is doing his husbandly duty to downplay the beef between his wife, Mariah Carey, and her "American Idol" judging partner Nicki Minaj ... telling our photog the whole thing has been blown out of proportion.

Nick broke out his thesaurus when we caught up with him at the Santa Monica Pier today as he tried to deflect attention away from the confrontations between Mariah and Nicki.

As a host of a talent show of his own, he managed to turn the question around and try and direct the focus on the good things that come from shows like "Idol" and "America's Got Talent."

Despite what Nick thinks, Mariah takes this beef very seriously. She told Barbra Walters earlier this week that she has hired extra security after Nicki threatened to shoot her.

Steven Tyler thinks the entire Nicki Minaj/Mariah Carey beef is being orchestrated by the show for ratings ... and as a former judge on the show, he's one to know.

Our photog spotted the Aerosmith rocker last night leaving an L.A. restaurant -- it's called Son of a Gun (we like the name) -- and when we asked him if the entire feud was BS, he scoffed and said ... well, watch the video and you'll see.

And just in case you had hopes the scarfed one might make an "A.I." return some day ... Tyler proclaimed he'd never go back.

It's not safe for a delicate person like him.

"American Idol" could be a big hit ... apparently much to the dismay of producers who are trying to tame Mariah Carey and Nicki Minaj. So we gotta ask ...

Nicki Minaj was supremely disrespectful to Mariah Carey 2 years before she exploded on the set of "American Idol" this week ... TMZ has learned.

Nicki and Mariah teamed up in 2010 for a music video -- "Up Out My Face."  Nicki wasn't nearly as big at the time -- Mariah was, and we're told she felt like she was helping launch Nicki's career.



B. Scott, who's big on the Internet, appeared in the video.  He tells TMZ ... "Mariah went out of her way to be nice to Nicki and make her comfortable." But B. Scott says Nicki was a raving bitch, "making faces at her [Mariah] laced with rude comments under her breath." 

B. Scott says he blew the whistle on Nicki by giving Mariah the low down. B. Scott says Mariah decided not to confront Nicki and acted as if nothing had happened.

A source close to Nicki tells TMZ ... B. Scott is a liar because, "He works as Mariah's stunt double and of course he would say things like that.  He's worked for her for years."

B. Scott says he stayed in touch with Mariah and spoke with her Thursday night. Mariah says she wants to bury the hatchet with Nicki on "A.I." and focus on the contestants. 

Good luck with that.

Mariah Carey got a full police AND umbrella escort on her way out of an "American Idol" photo shoot in Baton Rouge yesterday -- 'cause the only thing more harmful than angry rappers are those damn UV rays.

Carey had told Babwa Wawa that she bulked up her security team after Nicki Minaj allegedly threatened to shoot her with a gun during their blowup earlier this week ... and Thursday she proved she ain't messin' around.

Sources tell us ... Mariah and Nicki both participated in the shoot -- and even posed for pics TOGETHER. We're told the shoot was peaceful, but it's clear the hatchet is not buried.

Tomorrow, the gang has another round of auditions ... and that's when tensions really start to heat up.

Stay tuned ...

"The Voice" judge Cee Lo Green is calling BS on Mariah Carey and Nicki Minaj's fiery feud -- telling TMZ, we're in L.A. ... practically EVERYTHING is fake in this town.

Cee Lo had just finished lunch in West Hollywood yesterday when we asked if he thought Nicki and Mariah's "Idol" fight was legit -- and he said, "This is Hollywood, California. Hardly anything's legit."

As for a possible "American Idol" ratings boost following the Nicki/Mariah fight -- Cee Lo says he's not worried, claiming, "I'm not intimidated. I think it's entertainment for everybody."

Nicki Minaj and "Her f*cking Highness" Mariah Carey have been ferociously going at it on the set of "American Idol."

Question is ...


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Mariah Carey just made it clear -- TMZ was dead on when we reported Nicki Minaj threatened to shoot her.

Barbara Walters reported on "The View" today she spoke with Mariah, who said she was concerned because "Nicki walked off the set and multiple people heard Nicki say, 'If I had a gun I would shoot the bitch.'"



Walters says Mariah told her, for safe measure, she's hired extra security.

And, Walters adds, Mariah said Nicki has not apologized but told her she loves her ....HOWEVER, Nicki said they might be fighting again on "American Idol."

For her part, Nicki just tweeted, "I don't call tmz n Barbara Walters cuz I stand on my own two feet.  Never needed an army. God is good.  Insecurity is as cruel as the grave."

Minaj continued, "I guess it hurts 2 have the producers tell u to ur face that nicki is the best judge we've had since simon. Awww, poor u. Keep them lies cmn." So much for the truce.

As for Keith Urban (who was caught smack in the middle of the crossfire Monday) he told Extra yesterday he felt like "the UN" -- but added, "I love it, I gotta say. I love working with passionate people. I love artists. Everyone just sort of expressing themselves. It’s a very alive and very invigorating work environment."