Kim Yong Chol, the North's counterpart to Secretary of State Mike Pompeo in nuclear talks, was sent to a labour camp following the collapse of the Kim-Trump summit in Hanoi in February, South Korea's Chosun Ilbo newspaper had reported Friday.

But late Sunday Kim Yong Chol was among the country's top leaders - including Kim Jong Un, his wife Ri Sol Ju, senior members of the ruling party and top military officers -- at a "performance given by amateur art groups of the wives" of military officers, North Korea's official news wire KCNA said.

A picture carried by the official Rodong Sinmun newspaper showed the official sitting five seats down from Kim Jong Un, with both his hands covering his face.

South Korea's parliamentary intelligence committee in April said Kim Yong Chol had been censured over his handling of the Hanoi summit, despite the fact he had recently been named a member of the State Affairs Commission, a supreme governing body chaired by Kim Jong Un.

But Kim Yong Chol's name was included among those named by KCNA as attending the Sunday event.

Absent from the list, however, was Kim Hyok Chol, North Korea's special envoy to the United States who -- according to the Chosun Ilbo newspaper -- was executed by firing squad for "betraying the supreme leader" after he was "won over to the US" during pre-summit negotiations.

Kim Hyok Chol was the North's counterpart of US special representative Stephen Biegun in the run-up to the Hanoi summit.

Some previous South Korean reports of North Korean purges and executions have later proved inaccurate.