WASHINGTON (Reuters) - U.S. President Barack Obama on Thursday sent a request to Congress for an additional $11.6 billion in supplemental war-related funding, which would include money to fight Islamic State militants and sustain high overseas troop levels. The request, detailed in a letter released by the White House, seeks an additional $5.8 billion for the Pentagon for military operations in Afghanistan and fighting Islamic State in Iraq and Syria, and an $5.8 billion for the State Department and United States Agency for International Development (USAID) for fiscal 2017. Obama made the request just before Congress returns to Washington for its “lame duck” session before the new Congress starts in January. “For the Department of Defense, this plan reflects the evolving nature of our military campaign against ISIL and our efforts in Afghanistan,” U.S. Secretary of Defense Ash Carter said in a statement, using an acronym for Islamic State.  Carter added that the funding would also allow the State Department and USAID to counter extremism. “Swift passage of this plan will help the Department of Defense and our partners in the U.S. government and around the world protect this nation, and I urge Congress to support it,” the statement said.  U.S. Representative Mac Thornberry, the chairman of the House of Representatives Armed Services Committee, said he would review President Barack Obama’s request but that it was too low. “While we will review the request carefully, the amount still does not accommodate the increased pace of operations against ISIL and does nothing to begin addressing the readiness crisis,” Thornberry said in a statement. 