WASHINGTON (Reuters) - U.S. Ambassador to the United Nations Nikki Haley said on Tuesday that more sanctions on North Korea are unlikely to change the country s behavior but would cut off funding for its ballistic missile and nuclear programs.  Do we think more sanctions are going to work on North Korea? Not necessarily,  Haley told the American Enterprise Institute.  But what does it do? It cuts off the revenue that allows them to build ballistic missiles.  Haley said on Monday she wants the United Nations Security Council to vote on Sept. 11 to impose  the strongest possible  sanctions on North Korea over its sixth and largest nuclear test. 