BAGHDAD, Dec. 22 (Reuters) - An increased U.S. naval presence in the Gulf is not a response to any action by Iran but a message to all countries that the United States will keep its regional footprint "for a long time", U.S. Defense Secretary Robert Gates said on Friday.

CBS News reported on Monday that a projected naval buildup was intended to discourage what U.S. officials view as increasingly provocative acts by Tehran pressing for a nuclear program and support for Shi'ite militias in Iraq.