Defoe says he must gain international acclaim if he is to earn the tag of the world's best.
"To get that sort of accolade, you have to prove yourself in a massive tournament like the World Cup," Defoe told the Evening Standard.
"If you get an opportunity to be the best striker in the world, you won't do anything to jeopardise it. It's a World Cup year, so the situation is perfect."
England coach Fabio Capello's first choice front pair seems to be Emile Heskey and Wayne Rooney, but Defoe insists his slight stature - he is 5 ft 6.5 inches tall - should not count against him.
"If you look at the World Cups down the years, small players have been able to dominate the tournaments," he said.
"The Brazil side who won the 1994 World Cup had Bebeto and Romario in attack. In 1990, Italy had Salvatore Schillaci and Roberto Baggio.