The 30-year-old striker made his comeback from a knee ligament injury against Hamburg on Sunday, scoring in a 3-0 win.
While the Netherlands international remains focused on enjoying a successful second half of the season, he revealed a switch to England could be on the cards if he fails to agree a new deal at the Veltins Arena.
"I still have a one-and-a-half-year contract. I think half a year before the end it is decided how it goes," Huntelaar told Bild.
"Sure I think now and again of England. But now only Schalke count for me and the second half (of the season)."
Sunday's victory over Hamburg provided Huntelaar with his first taste of action since August, and saw Jens Keller's men climb to fifth in the Bundesliga.
The former Milan and Real Madrid striker is eager to play a part in Schalke's season, alongside attacking talents such as Max Meyer, Julian Draxler and Kevin-Prince Boateng, adding that he believes he can extend his career for another 10 years.
"When you play in a team where only one or two people want to score goals, that's way too easy to defend. You have to have goals even from midfield. As a striker, you need goalscoring people next to you," he added.
"I want to play to 40. I want to play another 10 years of football. I feel young and fit."
