The 20-year old Belgian international is keen to develop his game even further after winning 16 caps for his country and sees England as the major test.
"I am ready to go abroad," Defour told Het Nieuwsblad.
"But if Standard want me to stay, I'll stay.
"They're an amazing club but Standard Liege must decide whether they are good enough or not.
"I still have a contract until 2013. But if Standard refuse an offer, they have to give me something in return."