The 34-year-old's form over the last couple of seasons has seen him earn a recall to the England squad under Gareth Southgate, and it is understood that he is in the thinking of the Three Lions manager for the 2018 World Cup.
Defoe has admitted that he would have to consider leaving Sunderland at the end of the season if the club were relegated in order to give him the best possible chance of securing a spot in Southgate's World Cup squad.
"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," Defoe told reporters.
"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."
Defoe has scored 19 times in 55 caps for England, but has not represented his national team since 2013.