US President Barack Obama has met Chinese Premier Wen Jiabao on the last day of his visit to China. Trade disputes were expected to be on the agenda during Mr Obama's lunch with China's third-highest leader, who is responsible for the economy.<br/>Prior to their meeting, the two leaders said the relationship between the two countries was moving forward. Mr Obama was visiting China's Great Wall, before heading to South Korea.<br/>The US president – who is on a week-long tour of East Asia – is expected to focus on North Korea's nuclear ambitions during talks in Seoul.<br/>