U.S. President Donald Trump and First Lady Melania Trump walk across the South Lawn as they return to the White House in Washington, DC on May 28. AFP-Yonhap

U.S. President Donald Trump on Tuesday deflected criticism that he insulted a fellow American over a dictator when he agreed with North Korea's harsh assessment of Democratic presidential hopeful Joe Biden.

Trump has come under fire since he made remarks on Twitter and during a press conference in Tokyo over the weekend that supported North Korea's statement last week on the former vice president.

In a commentary published by the state-run Korean Central News Agency, Pyongyang slammed Biden as a "a fool of low IQ," apparently in response to the presidential candidate's labeling of Kim Jong-un as a tyrant and dictator.

U.S. Democratic presidential candidate and former Vice President Joe Biden runs up the steps onto the stage to begin the kickoff rally of his campaign for the 2020 Democratic presidental nomination in Philadelphia, Pennsylvania, U.S., May 18. Reuters-Yonhap