Foreign ministers from around 20 nations gather on Tuesday to discuss how to curb North Korea's nuclear ambitions through diplomatic and financial pressure, but China, seen as a key player in any long-term solution, will be absent.

The Vancouver meeting, co-hosted by Canada and the United States, comes amid signs that tensions on the peninsula have eased, at least temporarily. North and South Korea held talks for the first time in two years last week and Pyongyang says it will send athletes across the border to the Pyeongchang Winter Olympics.

But the United States and others say the international community must look at ways of expanding a broad range of sanctions aimed at North Korea's nuclear program.