This is due to the threat that was made by the Spanish FA to leave UEFA if they decide to suspend the European governing body UEFA to consider expelling its president Luis Rubiales from his office following the incident with Jennifer Hermoso.
If this threat becomes a reality this would mean all Spanish clubs Real Madrid and Barcelona would be excluded from UEFA competitions like the Champions League (also affecting Atletico Madrid and Real Sociedad), Europa League (Villarreal and Real Betis), and the Europa Conference League (Osasuna).