The striker, on-loan at Hearts, says Kenny Dalglish had a big influence on his decision.
He told the Scottish Sun: “I played for Manchester United in the Milk Cup youth tournament in Northern Ireland a few years back.
“I scored in the final and set up the other goal in a 2-1 win — so it was nice to be part of a successful team.
“Guys like Paul Pogba, Ravel Morrison, Will Keane and Joshua King were there and some young players who have featured for United this season.
“It was a good experience. United wanted to sign me but Kenny was the Liverpool academy manager and I ended up choosing them. I don’t regret it.
“Kenny was a big influence on me. We had a lot of conversations and he even used to come out and train with us from time to time.
“He was always around and passing on great advice for us all. He was absolute quality in training."