The 37-year-old footballer insists he ''didn't know anything about it'' after he was told about the speculation, 11 years after the superstar singer claimed she could be a relation of the former Chelsea defender.
When asked about the rumours on Thursday's (18.10.18) episode of game show 'A League of Their Own', he says: ''I'm not saying it's not true but I don't know. I don't know anything about it.''
Show host James Corden then reads him an article featuring a source which quotes him as being ''chuffed to bits'' about the news.
The TV presenter said: ''Listen to this, 'Ashley's chuffed to bits that they're related. He's always been a big fan of Mariah's, and grew up listening to jazz legends like Nat King Cole...''
But Ashley laughs and says: ''Oh no way, man.''
In 2007, Mariah claimed she could be related to Ashley after she discovered a possible link while searching for an ancestral connection to jazz legend Nat.
She said: ''It's fascinating. My grandmother was a Cole before she married and it turns out she comes from the same area of Alabama as Ashley's ancestors in the Deep South.
''We are still looking into it to see if we're also related to Nat King Cole. I'm such a huge fan of his. That would be wonderful, and would also explain so much.''
A spokesman for the ex-Arsenal star said at the time: ''I don't know if he's heard the Mariah story or not but I know Ashley was born and raised in east London.''
Ashley was married to Girls Aloud singer Cheryl at the time, and a spokesman for her claimed that she would look into the speculation because the performer is a ''huge fan'' of the star.
They said: ''I'm sure she'll look into it to see if there's any truth. She's a huge fan of Mariah's and watched her perform at G-A-Y in London the last time she performed there.''
Ahead of their upcoming tour, and prior to the release of their long awaited album, Smoke Fairies played a great warm-up gig at Elsewhere in Margate.