A senior North Korean official who had reportedly been purged over the failed nuclear summit with Donald Trump has appeared in state media enjoying an art performance with Kim Jong-un.

Kim Yong-chol, who had been the North’s top nuclear diplomat and counterpart of Mike Pompeo, the US secretary of state, was shown sitting five seats away from the clapping North Korean leader.

They were seen with other top officials enjoying a musical performance by the wives of Korean People’s Army officers.

Last week, South Korean newspaper Chosun Ilbo cited an unidentified source who said Kim Yong-chol had been sentenced to hard labour and ideological re-education over the failed summit in the Vietnamese capital of Hanoi.

Negotiations broke down over what the US described as excessive North Korean demands for sanctions relief in exchange for only a partial surrender of its nuclear capabilities.

North Korea military parade celebrating nation's 70th anniversary Show all 18 1 /18 North Korea military parade celebrating nation's 70th anniversary North Korea military parade celebrating nation's 70th anniversary Participants wave flowers AFP/Getty North Korea military parade celebrating nation's 70th anniversary North Korea's leader Kim Jong Un (R) waves with China's Chairman of the Standing Committee of the National People's Congress Li Zhanshu (L) from a balcony AFP/Getty North Korea military parade celebrating nation's 70th anniversary Airplanes forming the number 70 fly in formation and fire flares AP North Korea military parade celebrating nation's 70th anniversary North Korean performers dance EPA North Korea military parade celebrating nation's 70th anniversary North Korean military officers applaud near portraits of late North Korean leaders Kim Il Sung and Kim Jong Il AP North Korea military parade celebrating nation's 70th anniversary North Korean tanks roll past AP North Korea military parade celebrating nation's 70th anniversary Participants cheer as they take part in a parade for the 70th anniversary of North Korea's founding day in Pyongyang, North Korea, Sunday, Sept. 9, 2018. North Korea staged a major military parade, huge rallies and will revive its iconic mass games on Sunday to mark its 70th anniversary as a nation. (AP Photo/Ng Han Guan) Ng Han Guan AP North Korea military parade celebrating nation's 70th anniversary Korean People's Army (KPA) soldiers take part AFP/Getty North Korea military parade celebrating nation's 70th anniversary Korean People's Army (KPA) soldiers march AFP/Getty North Korea military parade celebrating nation's 70th anniversary Participants march during a mass rally on Kim Il Sung square in Pyongyang AFP/Getty North Korea military parade celebrating nation's 70th anniversary A girl reacts during a parade AP North Korea military parade celebrating nation's 70th anniversary North Korean leader Kim Jong Un, right, reacts as he chats with China's third highest ranking official, Li Zhanshu AP North Korea military parade celebrating nation's 70th anniversary People carry flags in front of statues of North Korea founder Kim Il Sung (L) and late leader Kim Jong Il Reuters North Korea military parade celebrating nation's 70th anniversary Performers take part in a concert at the Pyongyang Indoor Stadium AFP/Getty North Korea military parade celebrating nation's 70th anniversary North Korean artillery roll past AP North Korea military parade celebrating nation's 70th anniversary Students perform Reuters North Korea military parade celebrating nation's 70th anniversary Soldiers march during a military parade Reuters North Korea military parade celebrating nation's 70th anniversary Participants wave flowers AFP/Getty

The newspaper also reported that Kim Hyok-chool, the North’s working-level nuclear envoy to the US, was executed with four other officials for betraying Kim Jong-un after being won over by the US.

Mr Pompeo said he had seen the report and the US was “doing our best to check it out”.

Pyongyang’s stringent control of information has made it difficult for the South Korea’s government and media to track developments among the North’s ruling elite.

Kim Yong-chol had been described as Kim Jong-un’s right-hand man and previously worked as a military intelligence chief.

Donald Trump is not 'bothered' by North Korea missile tests

During denuclearisation talks with the US last year, he travelled to Washington and met Mr Trump twice before the US president met Kim Jong-un.