The head of the World Trade Organization said Thursday he will leave his post a year before his term expires, an unprecedented mid-term resignation at the WTO that he called a “personal decision.” Roberto Azevedo, a former diplomat from Brazil, said he will step down on Aug. 31, cutting short a seven-year tenure marked in recent years by intense pressure from U.S. President Donald Trump, who accused the Geneva-based trade body of an anti-U.S. bias and other complaints. “This is a decision that I do not take lightly,” Azevedo told a special meeting of WTO delegations. “It is a personal...