D.Boerse, NYSE see extra $1 billion in customer savings

A U.S. flag flies outside the entrance to the New York Stock Exchange in New York, July 7, 2011.

(Reuters) - Deutsche Boerse AG (DB1Gn.DE) and NYSE Euronext (NYX.N) said they now expect up to an additional $1 billion in broad savings for customers if they are able to seal their $9 billion merger and create the world's largest exchange operator.

The pair expect "collateral efficiencies" of up to $4 billion, Deutsche Boerse spokesman Ruediger Assion said in an email. That is up from the approximately $3 billion that was touted as recently as an August 2 NYSE Euronext presentation.

The new prediction comes as the takeover of the New York Stock Exchange parent faces an intense antitrust review in Europe. On Thursday, Europe's competition chief expressed concern that the deal would create a monopoly in derivatives.

(Reporting by Jonathan Spicer in New York; Editing by Steve Orlofsky)