Sunderland fans have slammed former X Factor contestant Wagner after he branded them "inbred".
The 62-year-old entertainer charges fans as little as £9.99 for custom Facebook videos.
In one of his latest clips, he made the slur against Black Cats ahead of the Checkatrade Trophy final at Wembley on Sunday.
And he added: "Enjoy your cheesy chips on Wembley Way you bunch of inbreds."
"The last time I seen you Sunderland fans, you were crying on Netflix."
Wagner, who has over 200,000 Facebook followers, insists the the comments were just "light banter".
On Facebook, Newcastle United fans branded Wagner "some boy" for the stunt.
It is widely suspected the star was put up to it by mischievous Toon supporters ahead of Sunday's final.
But Wagner told ChronicleLive: "I don't know if it was a Newcastle fan who ordered the video or not but I presume so.
"I allow light banter in my videos.
"There are certain things I won't allow but a bit of banter is OK - I keep my videos as fun as possible that's why they're popular.
"I'm glad Newcastle fans are loving the video, however if Sunderland fans are upset then why don't they order a video too?"
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When asked if he was sorry he called Sunderland supporters inbred, Wagner added he would only answer more questions if he was paid.
"I'm too busy recording mother's day video requests on top of all my other video orders now to answer anything else," claimed Wagner, who enjoyed a brief run on season seven of the ITV's X Factor.
But Sunderland fans - set to enjoy a trip to London this weekend - were not impressed with the star, or how he earns a living.
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"Personally, I would find something better to do for money and relevancy than having a go at Sunderland fans," said Ben Jewers, of Sunderland fanzine A Love Supreme.
"I live in Gateshead , so being a mackem there I get griefed about it daily.
"Stuff like this is standard, Newcastle fans are always like that, I feel they are always more vicious with their language - they are obessed."
This isn't the first time one of Wagner's clips has sparked anger.
In 2015, he apologised for singing "Oo-ahh, up the Ra!' - a pro-IRO chant - claiming he didn't know the context.
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