Porto stormed to the SuperLiga title in the recently-completed season, but their achievement was overshadowed by a six-point deduction they received for attempting to bribe referees during the 2003/04 campaign.
And a statement on the club's official website confirmed they would not play in Europe's elite club competition next season as a result of events four years ago.
"FC Porto was today notified by the UEFA Disciplinary Committee of the decision to not admit FC Porto to the 2008/09 edition of the UEFA Champions League," read the statement.
"FC Porto will appeal against this decision to the UEFA Appeals Body."
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