The France international has been heavily linked with a move to Jose Mourinho's side, with rumours suggesting the Red Devils are willing to line-up a world-record bid to lure the 25-year-old to the club.
Under the tutelage of Simeone, Griezmann has continued to impress since arriving at the Vicente Calderon from Real Sociedad in 2014 - netting 69 goals in 132 games in all competitions.
The Euro 2016 Player of the Tournament and top goal-scorer is said to have garnered interest from a number of top clubs around the globe and Simeone says he has no intentions of standing in any of his players' way if they want to make a move.
"I don't tie anyone down, I simply keep working to continue getting better for the sake of the club," he told Spanish publication AS.
"He is in an extraordinary moment, is working well, has gotten back on the score-sheet and his form is good.
"It is normal that the best teams in the world want him.
"I am not surprised that the teams who are looking are the ones who can afford him," he concluded.