"The players have made every attempt to reach an agreement on a fair and equitable share of the prizemoney," Vivian said in a statement on Sunday.
"Despite these intentions the club has consistently refused to negotiate in good faith.
"Throughout this process the players have proposed a number of solutions to assist in coming to a resolution, including mediation and arbitration.
"However, the club has been unreceptive and unwilling to work towards an agreement that sees the players fairly remunerated for their success in reaching the tournament as the Champions of Asia or reflects their increased workload.
"As a result of this the players, with the full support of the PFA, have unanimously taken the decision to consider their participation in the tournament.
"The players and the PFA remain committed to sitting down with the Wanderers management to negotiate an acceptable outcome for all parties."
The Wanderers are set to meet the might of Mexico, Cruz Azul, on December 14 at the Club World Cup and a win books a date with global superpower Real Madrid.
Western Sydney sit last on the A-League ladder, winless after nine rounds.
Their latest defeat came on Saturday night when they were beaten 2-0 by Adelaide.
Wanderers players not with the group in Adelaide left for Morocco on Sunday morning with the club posting a picture on social media of three Western Sydney squad members at Sydney Airport.
A tweet accompanying that picture on the club's official Twitter account said: "First flight is up up and away. FIFA Club World Cup awaits. Morocco here we come!"
- AAP
