The 20-year-old played for the senior team in last year???s World Cup finals in Brazil and Southgate is not certain whether Sterling should face another summer of competitive action this time around.
The England U21 manager said: “Realistically, Raheem has become a very important player for the senior team and for Liverpool.
“There is a huge demand on him. Part of my role is looking at the development of individuals and I’m not convinced another tournament in the summer would be right for him.
“Of course he is a super player and, from a selfish point of view, it would be easy to try and grab all of those. But we have to look at the bigger picture,”
England are on course to qualify for next summer’s European Championship in France so, by playing in the European U21 event in the Czech Republic in June, Sterling could end up playing in tournaments three years in a row.