WASHINGTON: US President Donald Trump on Monday (May 21) urged China to maintain tight control of its border with North Korea until he signs a denuclearisation deal with Kim Jong UN. Donald Trump, China’s President Xi Jinping, and North Korea’s leader Kim Jong Un at a railway station in Seoul AFP/KIM Sue-han Trump is scheduled to hold a landmark summit with the North Korean leader Jun 12 in Singapore, but Pyongyang recently has threatened to pull out over US demands for “unilateral nuclear abandonment.” “China must continue to be strong & tight on the Border of North Korea until a deal is made,” Trump tweeted, suggesting China may have eased up on enforcing economic sanctions against Pyongyang. “The word is that recently the Border has become much more porous and more has been filtering in.”, he wrote, adding he wants North Korea to be ‘VERY successful,’ but only once a deal has been reached on denuclearization,” he said. China is North Korea’s biggest trade partner, and Trump has called on it repeatedly to press Pyongyang to rein in its nuclear and missile programs. Besides protesting US disarmament demands, North Korea also angrily condemned joint US-South Korean military exercises, and last…