UNITED NATIONS - The UN Security Council will hold a meeting on Friday on the situation in Syria's Idlib province, where an expected government offensive could cause a humanitarian disaster, US Ambassador to the United Nations Nikki Haley said on Tuesday. In a news conference, Haley also said US President Donald Trump plans to host a high-level meeting of the Security Council about Iran during September, when the United States holds the rotating presidency of the 15-nation body.