A judge said Federal Reserve Chairman Ben Bernanke should be required to testify in the lawsuit by the former chief of American International Group Maurice Greenberg, against the U.S. over the insurer's 2008 bailout, Reuters reports.

Judge Thomas Wheeler of the U.S. Court of Federal Claims on Monday rejected the government's effort to keep Bernanke from being subjected to a deposition by Greenberg's Starr International Co.

Wheeler called Bernanke a "key witness" who can provide highly relevant testimony, given that he was a "central figure" in the decision to bail out AIG.