CME Group Inc. (CME) said Thursday it will start testing a long-delayed clearing platform for credit derivatives next week.

The exchange operator will begin test-clearing credit-default swap trades with a pilot group of dealer banks and buy-side participants as the exchange finalizes details of the service, according to Ken Vroman, CME's chief of corporate development.

The announcement follows CME's decision to drop a trade execution platform for credit derivatives in an effort to build support among dealers that control the majority of trade in the $31 trillion over-the-counter market.

CME is competing with rivals IntercontinentalExchange Inc. (ICE) and Deutsche Boerse's (DB1.XE) derivatives unit Eurex to clear credit derivatives transactions. Banks are seeking to route more swap trades through clearinghouses as regulators weigh reforms for over-the-counter markets.

Since launching its service in March, ICE has cleared more than $2 trillion in CDS contracts. That puts the Atlanta-based company far ahead of Frankfurt-based Eurex, which launched a European platform in late July, and CME, which has yet to announce a launch date as it works to secure support from dealer banks.

Speaking to analysts in Chicago on Thursday, Vroman said that CME has been in talks with six to eight dealers "for quite a long time."

"We're confident we'll be coming to closure with them in the near future," he said.

In mid-September CME announced that it had signed six buy-side firms as founding members of its credit derivatives clearing service, including Citadel Investment Group, which had developed the now-abandoned CDS trading solution in conjunction with CME.

Other buy-side members are AllianceBernstein Holding LP (AB), BlackRock Inc. (BLK), BlueMountain Capital Management, D. E. Shaw & Co. and Allianz SE's (AZ) Pimco.

-By Jacob Bunge, Dow Jones Newswires; 312-750-4117;