WASHINGTON, Nov. 20 (Xinhua) -- U.S. Defense Secretary Robert Gates met with President-elect Barack Obama's team on Thursday and started political transition at the Defense Department.

    The Pentagon said that Gates discussed some key issues the new government would face after being sworn in on Jan. 20 with leaders of the Obama transition team, John White and Michele Flournoy, said Bryan Whitman, a Pentagon spokesman.

    Meanwhile, other members of the Obama team, including several senior officials from Clinton's administration, were expected to move out into various parts of the Defense Department to review policies, operations and procedures, he said.

    Despite promises to ensure a smooth transition at the Defense Department, Gates has issued an order not to provide classified information on current military operations and plans, according to a Pentagon memo released by U.S. media.

    The three-page memo, named "further guidance," was sent to all top department civilian and military officials on Nov. 19, said a CNN report.

    It rules no disclosure of "sensitive information" to the transition office, including "current military operations, special access programs, predecisional budget information, contingency operations; personal records, privileged and other legally protected information, competition sensitive information, and active National Security Council policy deliberations."

    The memo also said that transition team members who already have security clearances can have access to other classified information.

    Although the Defense Department is undergoing transition, Gates himself was considered to stay in Obama's administration.

    However, the 65-year-old former director of the Central Intelligence Agency has remained silent on the circumstances under which he would stay.

Special Report: U.S. presidential election 2008