China warned “major” differences remained on solving the 19-month-old standoff over North Korea’s nuclear program, as talks in Beijing appeared to reveal a toughening of positions. “There still exist differences between each side in some areas, and sometimes the differences are major,” Chinese foreign ministry spokesman Liu Jianchao told a regular briefing Thursday. At the start of the working-group discussions at the Diaoyutai Guest House in the western part of the capital, US and North Korean envoys showed little willingness to compromise, according to reports. “Their positions look even tougher now than a few days ago,” a diplomatic source told Russia’s ITAR-TASS news agency. Full Story