Attorney General Eric Holder announces resignation

President Obama: AG Holder resignation bittersweet
President Obama: AG Holder resignation bittersweet   

President Barack Obama announced the resignation of Attorney General Eric Holder on Thursday.

Holder will leave the Justice Department after nearly six years of leadership, and he has agreed to remain in his post until the confirmation of his successor, Obama said.

"Over the summer Eric came to me and said he thought six years was a pretty good run," Obama said, adding that he liked Holder for the job because the outgoing attorney general thinks "justice is not just an abstract theory, it's a living an breathing principle."

President Barack Obama stands with Attorney General Eric H. Holder Jr. who announced his resignation today, September 25, 2014 in Washington.
Getty Images
President Barack Obama stands with Attorney General Eric H. Holder Jr. who announced his resignation today, September 25, 2014 in Washington.

The first African American to hold the attorney general position, Holder is one of the last few officials who have stayed in their posts since the beginning of Obama's presidency. He is the fourth-longest serving attorney general in U.S. history.

Obama highlighted some of Holder's achievements during his tenure, including overseeing hundreds of terror cases, the largest mafia take down in American history, and helping to "safeguard our markets from manipulation and consumers from financial fraud."

"We could not be more grateful for everything you've done," Obama said to Holder at the press conference announcing the resignation.

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For his part, Holder thanked the president, saying "we have been great colleagues, but the bonds between us are much deeper than that—you have been there for me."

Last week, Holder said in a speech that he promised to bring charges against individuals on Wall Street with evidence of criminal conduct, especially relating to the financial crisis.

Pres. Obama: Holder's done superb job
Pres. Obama: Holder's done superb job   

Congressional Republicans have wanted to dismiss Holder for his involvement with the Fast and Furious gun operation, the IRS targeting scandal, and other high-profile controversies.

A New York City native, Holder became deputy attorney general in 1997 under the Clinton administration, and was U.S. attorney for the District of Columbia. He was also nominated by former President Ronald Reagan in 1988 to be an associate judge of the superior court of the District of Columbia.

NBC News contributed to this report.