By Gram Slattery and Humeyra Pamuk
UNITED NATIONS, Sept 22 (Reuters) – Donald Trump is set for a whirlwind schedule of meetings with leaders from four continents at the UN General Assembly on Tuesday, against the backdrop of an unstable Middle East and a four-and-a-half-year-old war in Ukraine that shows no signs of abating despite the US president’s repeated attempts at mediation.
