Chinese Premier Wen Jiabao today left Japan after meeting Japanese Emperor Akihito at the imperial palace, ending a three-day visit to Tokyo. Officials said, on Monday’s talks, Wen and Prime Minister Yukio Hatoyama agreed to set up a hotline following a series of naval incidents, and to resume formal negotiations on jointly exploring offshore gas and oil fields. Japan and China, the world's second and third-biggest economies, are rivals for resources and have competing claims to parts of the East China Sea.