A statement signed by organisations including UEFA, FSE and Fifa said: "There is no place for any type of 'super league' in Europe. Sporting merit is what counts.
"Football is for everyone. Keep it open to all."
FSE released a separate statement that read: "Their [Super League] aim remains to ensure a few select clubs receive the relative certainty of playing European football each year as well as the revenue that would bring. Participation in European club competitions is and must always be based 100% on sporting merit each season, without exception."