The Champions League finalists fear their side may break up during the close season with Mario Gotze already on his way Bayern Munich and Robert Lewandowski rumoured to be joining him.
Subotic has been linked with a move to the Premier League in the past, with Manchester United and Manchester City reportedly monitoring his progress.
The 24-year-old former Mainz youngster only signed a new contract in January that ties him to the Westfalenstadion until 2016.
He has dismissed rumours of a move away, saying he is happy with Jurgen Klopp's side and sees no reason to leave them in the summer.
"In January I signed a new three-year deal and I plan to stay," the Serbia international told Happy TV. "It is a great risk when a player changes his club -how will you get around, who will be your manager, how long will you remain, how many of the players will be sold. Because of all that I really believe that Dortmund is the best club for me.
"I have had the same manager for the last five seasons, the players don't change a lot and that is so important in football."