Kim used to call Biden 'mentally retarded' person, but said nice things for me: Trump

US President Donald Trump claimed that North Korean leader Kim Jong-un used a derogatory term to describe ex-President Joe Biden’s mental fitness. "He said very nice things about me...He used to call...Biden a mentally retarded person," Trump said. "But to me, he likes Trump. And do you notice how nice things are with North Korea? It's very nice," he added.