MOSCOW  -- A North Korean diplomat has said that Pyongyang will not return to multilateral talks until it resolves issues with the United States, a source said Sunday.

Choe Son-hui, director-general of the North American department of North Korea's foreign ministry, made the remark during a session at an international forum on nonproliferation in Moscow on Saturday, according to the source who attended the event.

The current crisis on the Korean Peninsula is due to the United States' hostile policy against the North, she said, adding Pyongyang will not return to any multilateral talks, including the six-party talks, until it deals with Washington, according to the source. 

Choe said the North will continue developing its nuclear program if the US does not give up on its hostile policies toward Pyongyang, according to the source.

Tensions have heightened since the North defiantly conducted its sixth and most powerful nuclear test last month, drawing strong condemnation from the international community.

North Korean leader Kim Jong-un has vowed to take the "highest-level" measures against Washington as Trump threatened to "totally destroy" the North if the US is forced to defend itself and its allies. Trump called the North's ruler Kim "Rocket Man," and Kim dubbed Trump a "dotard."

The conference was attended by diplomats, former government officials and private-sector experts from around 40 countries. As South Korea sent its deputy nuclear envoy to the event, it raised expectations that there could be contact of some type between the two Koreas, but it did not take place. (Yonhap)