UEFA president Aleksander Ceferin says a European Super League "will not happen."
Ceferin and Andrea Agnelli, chairman of the European Club Association that represents more than 200 top teams, have made their positions clear following a report that a leaked document revealed secret discussions taking place over a possible new league competition.
"The Super League will not happen," Ceferin told BBC Sport. "It is in a way a fiction now or a dream.
And Juventus chairman Agnelli added: "I can confirm we have never seen, never discussed, never been involved in the creation of this document.
"We are fully engaged with UEFA in shaping the game going forward."
Both men insist that Europe's leading clubs will remain part of UEFA, while also holding plans that could redraw the European football landscape from 2024.
Ceferin said: "We have some ideas. All I can say is that any Super League is out of the question. Participation stays. And everybody will have an opportunity to compete in every European competition."