interest costs made known to the United States Government by such organization for loans incurred on or after October 1, 1984, through external borrowings. Contributions for international peacekeeping activities For necessary expenses to pay assessed and other expenses of international peacekeeping activities directed to the maintenance or restoration of international peace and security, $529,909,000, of which 15 percent shall remain available until September 30, 2019: Provided , That none of the funds made available by this Act shall be obligated or expended for any new or expanded United Nations peacekeeping mission unless, at least 15 days in advance of voting for such mission in the United Nations Security Council (or in an emergency as far in advance as is practicable), the Committees on Appropriations are notified of: (1) the estimated cost and duration of the mission, the objectives of the mission, the national interest that will be served, and the exit strategy