James Comey, the former FBI director, gave ABC News an interview on his relationship with President Donald Trump.

Trump fired Comey last year as the FBI started in earnest to investigate the Trump campaign's ties to Russia.

A teaser of the exchange with ABC News suggests he referred to Trump as a "mob boss."

The full interview is scheduled to air this weekend.

James Comey likened President Donald Trump to a "mob boss" in an interview with ABC News.

Comey, whom Trump fired as FBI director in May, apparently described the president that way in an exchange with the ABC anchor George Stephanopoulos, a teaser clip of which emerged on Twitter early Thursday morning. The clip showed Stephanopoulos putting a series of questions to Comey.

"Was President Trump obstructing justice?” Former FBI Director James @Comey sits down with @ABC's @GStephanopoulos for an exclusive interview airing Sunday night at 10/9c on ABC. https://t.co/IE4XwxvIih #Comey pic.twitter.com/jNW3RUSVTi — ABC News (@ABC) April 12, 2018

His first is: "How strange is it for you to sit here and compare the president to a mob boss?" It cut to a different question before Comey responded.

It isn't clear whether Comey used the term "mob boss" in his description or whether that language belonged only to Stephanopoulos.

The interview, set to air in full this weekend, is part of a public-relations tour to promote Comey's book, "A Higher Loyalty," which is due to be published Tuesday.

Comey was fired as the FBI investigated Russian meddling in the 2016 US election and whether the Trump campaign colluded with Moscow.

Trump, who is also facing an obstruction-of-justice investigation stemming largely from his firing of Comey, has denied doing anything improper and has attacked Comey's integrity in the past. On Wednesday he again dismissed the FBI investigation, now led by a special counsel, as a plot headed by people with serious conflicts of interest.

The interview scheduled to air on ABC at 10 p.m. ET on Sunday. It was recorded Monday at Comey's home.

The day after the recording, Comey posted an image of the interview set on his Twitter account, while Stephanopoulos described the exchange as "quite a day."