The South Korean National Security Adviser (SKNS), Mr. Jeong briefed the public that the North Korea–United States summit would be held sometime in May 2018. The White House announced that the UN Sanctions would remain in place until an agreement between the United States and North Korea is reached. On March 6, Sarah Sanders said that the White House would need to see "concrete and verifiable steps" toward the denuclearization of North Korea before Trump would meet with Kim Jong-un. Later that day, an unidentified Trump official told "The Wall Street Journal" that Trump had still accepted Kim Jong-un's invitation. South Korea's national security adviser Chung Eui-yong visited China on March 12 to meet with the Chinese leader, Xi Jinping, of the foreign officials and report on the planned inter-Korean summit as well as the North Korea-United States summit and asked their advice. Russia on March 14, 2018, for explaining North Korea and the United States Visit Summary, seeking guidance for upcoming 2018 inter-Korean summit. National Information Director Suh Hoon visited Japan and had a consultation with Prime Minister Shinzō Abe including the foreign officials about the denuclearization and Permanent Peace on the Korean Peninsula. South Korea's foreign ministry announced on March 18 that selected informal delegations from North Korea, South Korea, and the US would meet for denuclearization discussions in April in Vantaa, Finland. (This type of discussions, as held previously, had sometimes been referred to as track-2 talks.) According to South Korea's "Yonhap" news, Choe Kang-il, a deputy director general for North American affairs at North Korea's foreign ministry, would also attend the event, which "Yonhap" termed "track-1.5 talks". North Korea's supreme leader Kim was in Beijing on March 25–28, 2018, arriving by special train for talks with China's paramount leader Xi Jinping, Kim's first known out-of-country excursion since taking power six years previously. China stated that North Korea was "committed to denuclearization" and willing to hold a summit with the United States. It was organized by the invitation of Xi. During the meeting between two leaders, Kim officially invited Xi to the North Korean capital Pyongyang when it was convenient in his schedule, and Xi accepted the invitation. Xi urged Kim to strengthen the strategic and diplomatic future partnership between China and North Korea. Kim stressed to Xi that North Korea and China are communist countries and that there are many ways to cooperate in various aspects in the future.