The 19-year-old winger has enjoyed an impressive campaign with the Reds, netting six Premier League goals from 24 appearances and establishing himself as a key part of Brendan Rodgers' plans.
Sterling, who made his Liverpool debut aged 17 in 2012, has two England caps to his name and he claimed the Man of the Match award in the recent 1-0 win over Agger's Denmark side at Wembley.
Roy Hodgson will choose his 23-man squad for Brazil on May 13 and Agger believes that Sterling is deserving of an inclusion.
"He can handle the pressure. Otherwise, he would not play for Liverpool. It is a fantastic opportunity for him," he told Politiken.
"In case he continues like he is doing right now, I can't see any reasons why he should not get a place in the squad for the World Cup."
"He is a big talent and got qualities that England need.
"Everyone can see that he is very quick and he is technically skilled, too. He has got experience from the best league and that is what really matters for a young player like him.
"To come on and get some matches to prove yourself. In any case, he got what you need to deliver."