Chong made the admission after starring in Holland's 5-1 victory over Cyprus U21.
"You discuss that with your family and the club and then you decide that it is better to stay with Manchester United," Chong said.
But he also left the prospect of returning to Feyenoord open.
"You never know in football," he emphasised. “It's hard to say what is going to happen now. The season has just begun so the focus is really on Manchester United. But of course you never know what can happen."