Chinese President Xi Jinping and Brazilian President Luiz Inacio Lula da Silva agreed on Sunday night to accelerate negotiations for a trade agreement between China and Mercosur, a striking reversal for Brasilia, which for years led resistance to such a deal in the South American bloc. The two leaders spoke by telephone for more than an hour, according to a statement from the Brazilian presidency, and “coincided on the importance of speeding up the talks for a Mercosur-China agreement that...