US Secretary of State Rex Tillerson arrived in Beijing on Saturday for his first face-to-face talks with Chinese leaders expected to focus on North Korea's nuclear programme, trade and South China Sea territorial disputes.
Tillerson's visit followed his remarks in South Korea on Friday in which he warned that pre-emptive military action against North Korea might be necessary if the threat from their weapons programme reaches a level "that we believe requires action."
China, the North's biggest source of diplomatic support and economic assistance, has yet to respond to his remarks, although Beijing has called repeatedly for steps to reduce tensions.
Chinese Foreign Minister Wang Yi, with whom Tillerson met Saturday afternoon, warned last week that the North and Washington and Seoul were like "two accelerating trains" headed at each other, with neither side willing to give way.
Tillerson's comments in Seoul that "all of the options are on the table," including possible military action, are likely to be deeply disconcerting to Beijing, which fears that a collapse of Kim's regime would send waves of refugees into northeastern China and land South Korean and American forces on its border.
In a further sign of its frustration with Pyongyang, China last month banned imports of North Korean coal for the rest of the year, potentially depriving Kim's regime of a key source of foreign currency.
Tillerson's visit to Beijing is the final stop on his three-nation swing through Northeast Asia, which began in Japan. State Department officials have described it as a "listening tour" as the administration seeks a coherent North Korea policy, well-coordinated with its Asian partners.
Tillerson said Saturday that the U.S.wanted positive ties based on "non-confrontation, no conflict and mutual respect."
He is expected to discuss with China its claim to virtually the entire South China Sea, including its building of islands atop coral reefs, complete with airstrips and military installations.