The musicians dated way back in 2010 but it didn't work out, prompting Taylor to release a song called 'Dear John' and John to record one called 'Paper Doll'.
That's all in the past, however, according to John.
In a new interview with Ronan Farrow on MSNBC, the singer-songwriter had nothing but praise for Taylor professionally.
He said it was great Taylor had such a massive reach with her fanbase and could use that to bring awareness to things.
Not just Taylor, he also spoke about artists like Kanye, saying certain artists control all the media which is brilliant when they can use their star power for good.
John touched on his former relationship with Taylor while talking about the track 'Paper Doll', saying: "The song never got listened to as a song. It became a news story because of the lyrics."
When it was pointed out surely he must have known that would happen, John answered: "I'm not in the business of telling people what the song is about. I never said anything about it.
"And now I just go, 'Look, I can say the name Taylor Swift. She's an artist. I'm an artist. Let's just everybody stop. Nobody's got an incurable cancer. We're rich people who get to live out our dreams. Let's just stop it. I'm a musician who's bigger than one song or one record."
John's no stranger to high profile romances having dated the likes of Jennifer Aniston, Jennifer Love Hewitt and Jessica Simpson in the past.
He's also been in an on-off relationship with ex-girlfriend Katy Perry.
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