Former Vice President Joe Biden's campaign fired back at President Trump for agreeing with North Korean dictator Kim Jong Un on Monday that Biden was a "low I.Q." individual.

"The President's comments are beneath the dignity of the office," Deputy Campaign Manager Kate Bedingfield said in a statement on Tuesday. "To be on foreign soil, on Memorial Day, and to side repeatedly with a murderous dictator against a fellow American and former Vice President speaks for itself."

Mr. Trump tweeted over the weekend that the North Korean leader had said that Biden had a low IQ. "North Korea fired off some small weapons, which disturbed some of my people, and others, but not me. I have confidence that Chairman Kim will keep his promise to me, & also smiled when he called Swampman Joe Biden a low IQ individual, & worse. Perhaps that's sending me a signal?" the president tweeted Saturday. 

During a visit to Japan on Monday, Mr. Trump said he agreed with Kim's alleged assessment of Biden. "Well, Kim Jong Un made a statement that Joe Biden is a low-IQ individual," Mr. Trump told reporters. "I think I agree with him on that."

Monday was Memorial Day, a day reserved for remembering soldiers killed while serving. Biden's campaign waited to respond until Mr. Trump returned to the United States in deference to the holiday, according to a campaign aide.

At his official campaign kickoff last weekend in Philadelphia, Biden chided Mr. Trump for his close relationships with foreign leaders like Russia's Vladimir Putin and Kim Jong Un.

"Are we a nation that embraces dictators and tyrants like Putin and Kim Jung Un?" Biden asked his crowd. "No!" many shouted back.

"Tyrants and dictators all over the world are using Trump's language to stifle dissent and solidify their own power," Biden continued.