London and New York--Embattled auditor Arthur Andersen continues to unravel as Ernst & Young L.L.C. said Friday it had reached an agreement to merge its New Zealand operations with its Big Five rival. The move comes one day after Andersen teams in Hong Kong and China said they would join with PricewaterhouseCoopers, while Ernst & Young said it planned to absorb Andersen's Russian business. The agreement is at odds with comments on Thursday from Andersen--which is now fighting the U.S. Department of Justice over its role in the collapse of U.S. energy trader Enron Corp.--that international partners are not at liberty to bolt the firm. Meanwhile, Houston-based Waste Management, the nation's largest trash hauler, and Chicago Mercantile Holdings, parent of the Chicago Mercantile Exchange, said they planned to drop Andersen. Andersen Worldwide, the Switzerland-based umbrella organization that represents Andersen's 85,000 employees around the globe, is seen as vulnerable because of the woes of its key U.S. component.