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Input: UNITED NATIONS (Reuters) - The United States will seek to boost its case for United Nations action against Iran when Security Council envoys visit Washington on Monday to view pieces of weapons that  U.S. Ambassador Nikki Haley  says Tehran gave to Yemenâs Houthi group.
 Haley  and  her  14 council colleagues will also lunch with President Donald Trump  the U.S. Mission to the United Nations said Friday.
The U.N. ambassadors will visit a military hangar at Joint Base Anacostia-Bolling near Washington  where  Haley   the U.S envoy to the United Nations  last month presented remnants of what the Pentagon said was an Iranian-made ballistic missile fired from Yemen on Nov. 4 at Saudi Arabiaâs capital Riyadh  as well as other weapons.
 Haley  said last month  she  was exploring several U.N. options for pressuring Iran to âadjust their behaviorâ. But  she  is likely to struggle to convince some Security Council members  like veto powers Russia and China  that U.N. action is needed.
 Haley  has said the Security Council could strengthen the provisions in that resolution or adopt a new resolution banning Iran from all activities related to ballistic missiles. To pass  a resolution needs nine votes in favor  and no vetoes by the United States  Britain  France  China or Russia.
Diplomats  speaking on condition of anonymity  say  Haley  has not signaled which accountability option  she  might pursue or when.

U.S. seeks to boost case against Iran with U.N. Washington visit