U.S. Defense Secretary Robert Gates has warned U.S. adversaries against trying to take advantage of president-elect Barack Obama when he takes office next month.

Gates told a gathering of Gulf state leaders in Bahrain Saturday that Mr. Obama will be "ready to defend the interests of the U.S. and its allies" from the moment that he steps into office on January 20.

The defense secretary said anyone planning to test the resolve of Mr. Obama's  administration would be "sorely mistaken."

Gates also singled out Iran for criticism, repeating a frequent White House claim that Tehran is trying to destabilize Iraq and the whole region.  He called on Gulf states to support the U.S.-backed government in Baghdad as the best way to counter Iran's influence.

Mr. Obama has asked Gates to remain in office when the government changes hands in January.  The move is expected to increase stability during the transitional period.

Some information for this report was provided by AFP, AP and Reuters.