Updated

Sen. Charles Schumer, the Senate’s top Democrat, came out Thursday against Republican colleague Jeff Sessions for attorney general.

Calling Sessions a “colleague” and “friend,” Schumer nevertheless said he could not support the Alabama senator for the Trump administration post.

“After reviewing his record and giving careful consideration to his answers during the hearing, I am not confident in Senator Sessions’ ability to be a defender of the rights of all Americans, or to serve as an independent check on the incoming administration,” Schumer, D-N.Y., said in a statement. “I am also deeply concerned by his views on immigration, which I saw firsthand during the push for comprehensive immigration reform. For those reasons, I will oppose his nomination to serve as the next Attorney General.”

The statement follows a sustained campaign against Sessions by his critics, including the unprecedented testimony of a Senate colleague – Sen. Cory Booker, D-N.J. – against him during Wednesday’s hearing. Booker testified that Sessions “has not demonstrated a commitment to a central requisite of the job … to aggressively pursue the congressional mandate of civil rights, equal rights and justice for all of our citizens.”

Critics charged the New Jersey senator was merely burnishing his credentials for a presidential run, with Sen. Tom Cotton, R-Ark., writing on Facebook he was “disappointed” Booker “has chosen to start his 2020 presidential campaign by testifying against Senator Sessions.”

Sessions and his allies also have fought back against the accusations, many of which stem from allegations that first surfaced during his failed nomination to a federal court position in 1986.

During a lengthy hearing appearance on Tuesday, Sessions adamantly denied claims of harboring racial animus. He decried the “false charges” and said critics were painting a “caricature” of him.

Republicans senators have come to Sessions' defense. On "Fox & Friends" Thursday, Sen. Ted Cruz, R-Texas, reminded his critics that Sessions prosecuted Klansmen years ago.

Sessions is still likely to be confirmed, provided Senate Republicans hold together on the vote.