Ariana Grande's fans have slammed a YouTube blogger for branding the singer the "rudest celebrity" he has ever encountered, simply because she stopped following him on social media.

In a video posted online over the weekend (31Mar18), James Charles, who became CoverGirl's first male ambassador in 2016, recalled his interactions with the Side to Side hitmaker via Twitter early last year (17), insisting the experience was "really crappy".

"I went to her show here in L.A.," he began. "I posted a bunch of videos from the night, and she had DMed (direct messaged) me, like, 'Thank you for coming!' She was so sweet... She followed me and DMed me. She was like, 'I wish I knew you were coming. I would've loved to have you backstage.'"

Charles explained the sweet messages had been sent to him just weeks after he became embroiled in a number of "scandals", including posting racist comments online and joking that he was worried about travelling to Africa out of fears he would contract viral disease Ebola.

Ariana's fans are said to have taken issue with their exchange, and made the pop superstar aware of Charles' controversial behaviour, apparently leading the 24-year-old to quickly unfollow his account online.

"I sent back a strong-worded message to her," Charles continued, "and was like, 'You have 100 million fans. It's really disappointing that you'd stoop to the level of listening to people bullying me just to appease them, but OK.'"

However, his remarks have not been well-received by Ariana's devotees, who have been quick to defend the singer for doing what they insist was the right thing.

"so apparently Ariana is the rudest celebrity James Charles has ever 'met' just because she followed and unfollowed him in the same day," one person tweeted. "lmfao (laughing my f**king a** off) that boy is so annoying".

"james charles said ariana is the rudest celeb and 'appeases bullying' because she unfollowed him after HE tweeted racist things," wrote another fan, as a fellow Twitter user praised Ariana by adding, "is it just me or do i find it so cute that ariana unfollowed james charles because she didn't want to disappoint us by following a racist. wow i love her (sic)."

Ariana has previously demonstrated her intolerance for racism, allegedly firing one of her female backing dancers last September (17) after learning she had used the N-word on Instagram.

The star has yet to personally comment on Charles' comments.