“I have decided to withdraw my name from consideration for this nomination,” Lieberman wrote in the letter, which was sent to the president on Wednesday.
Lieberman had been reported to be the front-runner to succeed James Comey, who Trump fired suddenly on May 9.
However, according to recent US news reports, Trump had been tilting against choosing the former Democratic senator from Connecticut.
“With your selection of Marc Kasowitz to represent you in the various investigations that have begun, I do believe it would be best to avoid any appearance of a conflict of interest, given my role as a senior counsel in the law firm of which Marc is the senior partner,” Lieberman wrote.
In 2000, Lieberman was the vice presidential running mate of sitting Vice President Al Gore for the Democratic Party. They lost to George W. Bush and Dick Cheney though they received half a million more votes nationally.