Story highlights Lieberman cited the hiring of attorney Marc Kasowitz as posing a potential conflict of interest

CNN has learned the team tasked by the White House with finding a new director for the FBI is resetting its search

Former TSA chief John Pistole may be under consideration

(CNN) Former Sen. Joe Lieberman, once considered a front-runner to succeed James Comey as FBI director, formally withdrew his name from consideration Thursday.

In a letter to President Donald Trump that was obtained by CNN, the 2000 Democratic vice presidential nominee cites Trump's hiring of attorney Marc Kasowitz to represent him during investigations into alleged ties between his presidential campaign and Russia.

Lieberman, a senior counsel for the New York-based Kasowitz Benson Torres LLP, said it "would be best to avoid any appearance of athe interlocking network of alliances, trade rules and international organizations as beneficial to the United States.

But Mr. Trump has ripped up the Paris climate accord and the Iran nuclear deal — both of which were negotiated under the strong influence of world powers. He has also imposed tariffs on the United States’ closest allies and left the Group of 7 summit meeting this month in chaos and recriminations after he denounced Prime Minister Justin Trudeau of Canada as “very dishonest & weak.”

The Trump administration has made clear that it will not countenance the level of criticism and what it describes as slanted resolutions by the Human Rights Council that have historically been directed at the United States and Israel. On her first day as ambassador, Ms. Haley warned