Defoe said: "Obviously you have to be realistic and to get into any squad it is based on merit and you need to be playing at the top level.
"When I went to Toronto (in MLS in early 2014) I missed out on going to the World Cup and it was a hard call to take. I would say I probably need to be playing in the Premier League but we will see what happens.
"The boys I'm competing against are playing in the Premier League and playing in Europe and probably that's why I missed out on the last World Cup. You probably need to be playing in the Premier League.