The 29-year-old has been linked with a move to Scottish giants Rangers.
“I’ve spoken to the manager a few times and he’s reassured me that I’m part of his plans,” he told Sky Sports News.
“I’ll keep working. I still know where the goal is, as a striker you don’t forget that and hopefully come the run in, come the important games, I’ll be helping out with a few goals.
“People are aware I’ve been disrupted by injuries, but it doesn’t mean I want to leave Sunderland. It’s never crossed my mind that I would go and play for Rangers.
“It’s flattering at times to be linked with other clubs, obviously when I was at Fulham and wasn’t playing. But I’m a Sunderland player. It’s a huge club with huge potential.”