Donald Trump has said his former chief of staff, John Kelly, could have been one of the four anonymous sources used by The Atlantic in the publication's report that the president made disparaging comments about military troops.

"It could have been a guy like a John Kelly," Mr Trump said while calling the story a "hoax".

The president's response about his former chief of staff came after he was asked why General Kelly has not denied or confirmed the report in The Atlantic.

"I know John Kelly. He was with me. He had no temperament," Mr Trump said. He went on to say that Mr Kelly was "exhausted" and "unable to function" by the end of his time with the Trump administration.