The Chinese Premier, Wen Jiabao, is visiting South Korea amid continuing tension over the sinking of a South Korean warship in March, allegedly by North Korea. <br/> <br/>The issue is expected to dominate Mr Wen's talks with the South Korean President, Lee Myung-bak on Friday. <br/> <br/>International investigators have blamed North Korea for sinking the warship. But China has so far refused to join in the widespread condemnation of its old ally, Pyongyang. <br/> <br/>The Chinese state news agency Xinhua reports, the visit would strongly boost ties between the two countries.<br/>