One day before US President Donald Trump signed a presidential memorandum allowing the US Trade Representative to consider launching an investigation into "unfair Chinese trade practices", National Security Advisor H.R. McMaster said China's help was vital to resolving the Korean Peninsula nuclear issue and the United States was not looking for a trade conflict.

Refusing to link trade with the Democratic People's Republic of Korea's nuclear program, McMaster said the operative word is not "punish" but "to compete effectively", "to demand fair and reciprocal trade and economic relationships with not just China but with all countries".

The top US security advisor's remarks seem to be at odds with that of his president, who has time and again made that link. Briefing reporters last week, Trump spoke of losing "hundreds of billions of dollars" a year in trade with China, hinting that he would "feel a lot differently toward trade" if Beijing helped Washington counter Pyongyang.