ISLAMABAD, April 26 -- The latest ceasefire talks between the United States and Iran appeared to fail Saturday before they began, as Tehran's top diplomat left Pakistan and President Donald Trump soon afterward said he had told envoys not to travel to Islamabad. The negotiations were meant to follow historic face-to-face talks earlier this month between the US, led by Vice President JD Vance, and Iran, led by parliament speaker Mohammad Bagher Qalibaf. But Iranian officials have questioned how they can trust the U.S. after its forces started blockading Iranian ports in response to Iran's war grip on the Strait of Hormuz. In announcing his decision Saturday, Trump said on social media: "If they want to talk, all they have to do is call!!!" T...