WASHINGTON (AP) - Republican Sen. John Kennedy of Louisiana says he didn't enjoy taking down one of President Donald Trump's judicial nominees, but his job is to catch mistakes, "and that's what I did."

Kennedy became an internet sensation after questioning Matthew Petersen about basic legal knowledge. Petersen struggled and later withdrew his nomination after the humiliation.

MORE: Sen. Kennedy on Trump judicial nominee: 'He has no litigation experience.'

Kennedy says the president called him to say "look, Kennedy, do your job. I'm not upset or angry.'"

Kennedy has been a rare Republican willing to criticize a few of Trump's nominees.

Sen. John Cornyn, R-Texas, and a member of the Judiciary Committee, said Kennedy's tough questioning should be a teachable moment for the White House.

Democratic senators were elated. They've warned that some of Trump's judicial nominees aren't qualified.