EU asks China help on Iran, Syria Summary Box: EU asks China help on Iran, Syria CHINA APPEAL: European Union leaders urged China to open its markets, join in persuading Iran to negotiate over its nuclear program and help end bloodshed in Syria, as they held a summit delayed by Europe's debt crisis. PROMISES: Both sides pledged to boost trade and start talks on an investment treaty. But at a news conference, EU officials and Chinese Premier Wen Jiabao expressed differences on issues from trade to human rights. CLOSED DOORS: Europe is China's biggest trading partner but European companies complain Beijing limits access to promising industries and favors Chinese rivals in violation of its free-trade pledges.