Slovenia, which holds the EU's rotating presidency, said it wants the 27-nation group to sign a Stabilization and Association Agreement (SAA) with Serbia by the end of this month.
"I'm one of those who believe that the SAA should be signed as soon of possible, possibly by the end of this month," Dimitrij Rupel told a news conference.
He said the decision to set up the group had been made earlier on Tuesday in the course of his meeting with EU Enlargement Commissioner Olli Rehn and European Commissioner for External Relations and European Neighborhood Policy Benita Ferrero-Waldner.
Rupel said Serbia must cooperate fully with the International Criminal Tribunal for the Former Yugoslavia (ICTY) before actually signing the deal.
He said Belgrade must make every effort to capture fugitive war criminals, Bosnian Serb leader Radovan Karadzic and his army chief, Ratko Mladic, who have been indicted for genocide.