The 19-year-old has a release clause in his contract which would allow him to move to United for €60million this summer, while former club Manchester City have their own buyback option which could see them complete a deal for €46.5m.
"Obviously there are people talking, asking me and stuff but I am not really thinking about it," Matondo told the Manchester Evening News.
"I am concentrating on Schalke. I still have to achieve my goals for Schalke. I am just concentrating on that and we just see how things go, but for now I am just focused on Schalke.
"Hopefully I can get into the team and help them climb up the table."
When asked if a return to play in the Premier League was his ultimate club ambition the Welsh winger remained coy but admitted it wasn't something he'd ever rule out.
He added: "I haven't really thought about it like that.
"I just want to do well at Schalke and give back what they have invested into me.
"I just want to give my all and then whatever happens in the future happens. Never say never."