Tosic, who joined United from Partizan Belgrade in January, admits he is concerned over his place in the Serbian national side.
Tosic is yet to feature in the league for United this season.
“I am doing my best to break through at United but there are many good wingers in the squad and all I can do is keep working hard and take every given opportunity to play well,” Tosic told Reuters.
“I am not thinking about a move away from United because I am confident that I belong here and that if I am patient enough, I will be able to prove my worth and eventually break into the first team.”
“It would be easy to lose faith, get frustrated and make a hasty decision to go to another club, but I have joined one of the three biggest clubs in the world and I don’t want to spurn an opportunity to stay here,” he continued.
He added: “On the other hand, I have to keep in mind that I need more first team football to keep my place in the Serbia squad ahead of next year’s World Cup finals in South Africa.
“Time will tell, but I definitely want to stay.”