The move follows the request for resignation of the Dressage Committee by FEI president Princess Haya earlier this month.
At the forthcoming FEI General Assembly taking place in Buenos Aires, Argentina, from November 17-21, the Ad Hoc Working Group remit will be proposed for discussion and approval by the FEI Bureau.
The status of the members of the current Dressage Standing Committee, who have been called upon to resign, will be an issue for FEI member National Federations to address through the FEI Bureau and General Assembly as appropriate.
Proposed names of the Ad Hoc Working Group include: Frank Kemperman (NED), chairman and representative of the event organisers; Richard Davison (GBR), riders representative; Robert Dover (USA), trainers representative; Alain Francqueville (FRA), chef d'equipe. A further member representing the judges is being finalised.
However, two national federations, Denmark and Spain, have argued that Princess Haya cannot demand the immediate resignation of the FEI Dressage Committee because of FEI regulations.
"There is no dout that there has been mistakes from both the executive board and the committee, but most important is that rules and regulations must be respected," said Ulf Helgstrand, president of the Danish Equestrian Federation.
"Otherwise we will get a 'wild west' situation. The dressage committee has respected the rules and regulations, while the Executive Board has a problem, since the committee is elected and approved by the General Assembley. This means that the Executive Board with Princess Haya as President has no competence to demand the resignation of the dressage committee. On the contrary the Executive Board has the duty to respect rules and regulations wich have been democratly approved by the General Assembly."
A statement from the Spanish Equestrian Federation said: "Leaving aside the motives and reasons made public both by the President of the FEI as well as the Committee, the RFHE thinks it fundamental to remind that the FEI is a democratic institution, with internal functioning rules duly approved by the different bodies, that determine at all times the way its members must proceed.
"Based on this ... our federation can not agree with the decision made public by the Executive Board."