President Trump called it "bothersome" that the man investigating possible ties between his presidential campaign and Russia has been friendly with fired FBI director James Comey.

Mr. Trump remarked on "Fox and Friends" in an interview for Friday that special counsel Robert Mueller is "very, very good friends with Comey, which is very bothersome."

Comey was overseeing the investigation into any ties between Trump campaign associates and Russia until Mr. Trump fired him last month out what he has said is frustration with the inquiry.

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Asked whether Mueller should step down from the investigation because of his friendship with Comey, Mr. Trump replied, "We're going to have to see."

Mueller and Comey worked together during the Bush administration, when Mueller was FBI director and Comey was deputy attorney general, and they overlapped at the Justice Department, as well. Before Mueller was appointed FBI director in 2001, he served as a U.S. attorney, as well as assistant attorney general for the Criminal Division and acting deputy attorney general. Comey has also served as a U.S. attorney, from 2002-2003, and as a deputy attorney general from 2003-2005, during the Bush administration.

Mr. Trump said on Fox News that, "The people that have been hired [by Mueller in the special counsel's office] are all Hillary Clinton supporters," a reference to the fact that several on Mueller's special counsel staff members have donated to Democratic candidates. He then went further and claimed, "Some of them worked for Hillary Clinton," though he didn't identify any individual special counsel staffer.

The president then added, "Robert Mueller is an honorable man and hopefully he'll come up with an honorable solution."

Fox News Channel released excerpts late Thursday after interviewing the president at the White House.