Nov. 5 (Bloomberg) -- Ambac Financial Group Inc.'s bond insurance rating was cut four levels to Baa1 by Moody's Investors Service.

The insurance financial strength rating was cut from Aa3 to reflect Moody's view of ``Ambac's diminished business and financial profile resulting from its exposure to losses from U.S. mortgage risks and disruption in the financial guaranty business more broadly,'' the New York-based ratings company said in a statement today. The outlook for the ratings is ``developing.''

To contact the reporter on this story: Romaine Bostick in Washington at crichard5@bloomberg.net

Last Updated: November 5, 2008 16:33 EST