President Xi Jinping will attend a nuclear security summit in Washington next week, less than three months after an increasingly unpredictable North Korea claimed to have tested a nuclear weapon. The president will attend the fourth bi-annual nuclear security summit starting on March 31, the Chinese Foreign Ministry announced on Wednesday. It will be his second Nuclear Security Summit since coming to power and his second trip to the United States over the past 12 months. China ‘must prepare for war over North Korea’s rocket launch and nuclear tests’ The summit comes after North Korea claimed in January it had tested a hydrogen bomb, in an underground explosion which US observers measured at magnitude 5.1. China has been under pressure to impose stricter punishments on North Korea for its nuclear test and missile launches. It has agreed to a new round of United Nations sanctions, but critics are sceptical of its willingness to faithfully carry them out. University of Hong Kong US-China relations expert Professor Xu Guoqi said North Korea had become a major headache for the Chinese government. “If North Korea has already become a nuclear power that gives the United States a strong excuse to basically do something in South Korea or to strengthen Japan,” he said. Xu said that while North Korea had become a major problem for China it was difficult for the government to completely walk away from the rogue state. “China can never walk away from North Korea with honour, [but] to allow them to behave this way will drag everyone into a big mess,” he said. “There’s a Chinese saying - when you’re on the tiger’s back, it’s very hard to get off.” China’s mishandling of North Korea’s nuclear ambitions may come back to haunt it Foreign Ministry spokesman Lu Kang said in a statement that Xi would pay a state visit to the Czech Republic from March 28 to March 30 before going to Washington for the summit. He will wrap up his trip on April 1. Xi will join Indian prime minister Narendra Modi in attending the meeting. Russia told the United States in October 2014 it would not be attending the summit, saying it doubted its effectiveness. “We do not see added value coming out of these meetings,” Russian ambassador Sergey Kislyak said.