The Poland international is under contract with the German champions until 2019.
Lewandowski has been linked with a move to Real Madrid, while there were reports that Bayern were set to extend his contract until 2021, although there has been no follow up on this.
But the 27-year-old marksman says he is fully focussed on the upcoming Bundesliga season, and says he is not concerned that a new deal has not yet been offered to him.
"My contract theoretically expires in 2019, which is still a long time. My focus is on the preseason and season," he told Sky Sports News Germany.
"We can always have talks and find a solution, but it's not an important subject for me at the moment. My deal will hold valid for three years, it's best if everybody keeps calm for now."
The former Borussia Dortmund front man also says he is eager to work under new Bayern coach, Carlo Ancelotti.
"I only have to say good things about Carlo. He is a superb manager, I like his philosophy and new ideas," he said. "We have a very good understanding and I hope that we can win many titles this season.
"We all know what we have to do, which is important for us players. We all have a good communication with Carlo."