A suspect in the murder of the estranged half-brother of North Korea’s leader has claimed he is the victim of a conspiracy by Malaysian authorities attempting to damage the honour of North Korea.

Ri Jong Chol, a North Korean, accused Malaysia of using coercion to try to extract a confession from him.

Kim Jong-nam was murdered on 13 February at Kuala Lumpur International airport, after being assaulted by two women who Malaysian police believe smeared his face with VX, a chemical classified by the United Nations as a weapon of mass destruction.

The murder of Kim has soured relations between Malaysia and North Korea, which had maintained friendly ties for decades.

Ri told reporters outside the North Korea embassy in Beijing on Saturday that he was not at the airport on the day of the killing and knew nothing about the accusation that his car was used in the case.

Ri was in Beijing en route back to North Korea after Malaysia deported him.

His arrival at the Beijing international airport early on Saturday was greeted by a swarm of South Korean and Japanese reporters, but Ri was whisked away from the chaotic scene by Chinese police before he was able to make any statement.

Outside the embassy, Ri told reporters that he was presented with false evidence in Malaysia, and police showed him pictures of his family in detention. “I realised that this is a conspiracy, plot, to try to damage the status and honour of the republic,” Ri said.

South Korean intelligence and US officials say the murder was an assassination organised by North Korean agents.

Kim Jong-un’s regime meanwhile bristled at suggestions the US might relist it as a state sponsor of terror because of the assassination. “The US will keenly realise how dearly it has to pay for its groundless accusations,” said North Korea’s foreign ministry. There have been calls from some members of Congress to reinstate the listing, which was removed in 2008 by George W Bush as part of disarmament talks that proved unsuccessful.