A North Korean diplomat who was part of six-party talks aimed at ending the country's nuclear program arrived in China on Monday, where she is expected to attend a forum in which the U.S. nuclear envoy will take part, Kyodo News said.

If the diplomat does take part, it would be a rare gathering of experts from the six countries weeks after Chinese President Xi Jinping said he would like to see the six-party talks resume.

Isolated North Korea conducted its fourth nuclear test in January and a long-range rocket launch the following month in defiance of U.N. resolutions, prompting the U.N. Security Council to impose tough new sanctions.