A statement after a meeting of the committee in Zurich on Thursday reaffirmed FIFA's support for UEFA in excluding Sion, and urging all clubs and football associations to abide by the decisions of the Court of Arbitration for Sport.
Officials from Celtic and the other clubs in their Europa League group - Atletico Madrid, Udinese and Rennes - are due to meet UEFA in Geneva on Friday to present a united front against Sion.
The Swiss club were kicked out of the competition for fielding six players signed during a transfer ban, but have gone to the Swiss courts - including personal action against UEFA president Michel Platini and general secretary Gianni Infantino - to try to overturn the decision.
Platini absented himself from discussions at the FIFA executive committee today, after which the world body released a lengthy statement in support of UEFA.
The statement said FIFA had issued a resolution "supporting the decisions taken by UEFA confirming that the six players signed. during the last transfer period were not entitled to participate in the UEFA Europa League".
It also declared FIFA's support for the decision that "the matches in which these players participated have been forfeited as well as the decision of the Swiss Football League to suspend the six players and the opening of disciplinary proceedings against FC Sion".