Amid widespread calls for his resignation, Eliot G. Spitzer, the one time "Sheriff of Wall Street" announced that he will step down as governor of New York state at 11:40 a.m. EST, saying that he is "deeply sorry" that he "didn't live up to what was expected" of him.
"To every New Yorker I sincerely apologize," he said, "I look at my time as governor as what might have been."
His resignation becomes effective on Monday.
After a press conference in which Mr. Spitzer, with his wife at his side, he apologized to the public and to his family without mentioning any specific charges.
The Democratic first-term governor was implicated on Monday for patronizing a high-end prostitution ring.
Mr. Spitzer, who served as New York's attorney general from 1999 to 2006, made his name by going after individuals and companies for violations ranging from insider trading to securities fraud.
Some of the individuals he targeted included former American International Group Inc. chairman and chief executive Maurice "Hank" Greenberg, former New York Stock Exchange chairman Richard Grasso, and former NYSE board member and Home Depot co-founder Kenneth Langone.
On Tuesday afternoon, the state's Assembly Minority Leader James Tedisco, in an interview with CNN, threatened that state Republicans would begin impeachment proceedings if Mr. Spitzer did not resign within 24-48 hours.
Lieutenant Governor David Paterson will now become governor.
"As an elected official the governor has worked hard for the people of New York," said Mr. Paterson.
"My heart goes out to him and to his family at this difficult and painful time. I ask all New Yorkers to join Michelle and me in prayer for them."