The 29 year old has managed to score 48 goals for his country in 74 appearances, but he feels that it is time for younger talent to come forward and take their chance.
Speaking to the press in Bulgaria he said: "I feel exhausted and now there are many guys who can emerge from my shadow.
"For them the moment has come. You should always know when to stop. I haven't discussed it with my club team."
Berbatov added: "I guess it will come out in England and Sir Alex will call me."