UPDATE 1-Treasury mulling costs, benefits of TIPS issuance

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WASHINGTON, Sept 15 (Reuters) - The U.S. Treasury Department is studying whether the costs of issuing inflation-protected securities are high relative to issuing nominal securities, an official said on Monday.

"While the growth of inflation-indexed securities remains robust, and the importance investors place on them continues to grow, taking a step back, evaluating our practices, and examining the costs and benefits of any program in a deliberative manner is only prudent," Treasury Office of Debt Management Director Karthik Ramanathan said in remarks prepared for delivery to a conference in New York.

The cost of issuing Treasury indexed securities compared to nominal debt issued at a similar time was recently estimated at $30 billion, Ramanathan said.

Treasury officials are trying to understand why corporations are not issuing similar debt, and whether the U.S. government is selling insurance on inflation protection for too little, among other issues, Ramanathan said. (Reporting by Mark Felsenthal, Editing by Chizu Nomiyama)