Michel Platini has described the Court of Arbitration for Sport's decision not to overturn his ban from all football-related activity as a "profound injustice".
The court has reduced the Frenchman's ban from six years to four after hearing his appeal.
After the decision was announced, Platini confirmed that he will step down as UEFA president, but will continue to challenge the suspension.
The 60-year-old was initially banned for eight years after it came to light that he received an alleged "disloyal" £1.3m payment from former FIFA president Sepp Blatter, but the world governing body's appeals committee cut it down to six years in February.
Following today's announcement, Platini released a statement, which read: "I have noted the decision of CAS but continue to consider it a profound injustice. This decision imposes a suspension whose length would prevent me standing for the presidency of FIFA at its next election.
"As discussed with the national associations, I am resigning from my duties as president of UEFA while retaining the right to continue my fight before the Swiss courts to prove my innocence.
"Life is always full of wonderful surprises. I look forward to continuing to experience them."
Platini has been in office at UEFA since January 2007.