BEIJING (Reuters) - Chinese President Xi Jinping said on Friday that China will never allow its sovereignty, security and development interests to be undermined, adding that the Chinese people are not to be trifled with. Any act of unilateralism, monopolism and bullying would not work, and would only lead to a dead end, Xi said in a speech delivered at the Great Hall of the People in Beijing. Xi also called for moves to expedite the modernisation of the country’s defence and armed forces. He was speaking on the 70th anniversary of the deployment of the People’s Volunteer Army (PVA) to the Korean peninsula to help North Korea resist U.S.-led United Nations and South Korean forces during the 1950-53 war.