Former Vice President Joe Biden assailed one of his fellow Senate colleagues as a “dirty bastard” and a “son of a bitch” for blocking a major anti-busing bill in 1977.

Former Sen. James Abourezk (D-SD), who served in the Senate with Biden from 1973 to 1979, recalled the heated confrontation in his 1989 book, Advise and Dissent: Memoirs of South Dakota and the U.S. Senate.

According to the book, Abourezk was approached by the NAACP’s chief lobbyist, Clarence Mitchell, to lead the opposition to an anti-busing measure introduced by then-Sen. Biden. The legislation, authored by Biden and his then-colleague from Delaware Sen. William Roth (R), sought to prevent federal courts from ordering widespread busing. In particular, the NAACP was concerned about a provision allowing federal judges to only mandate busing to address existing segregation — essentially undercutting wider integration efforts.

Biden’s bill was in response to a court ruling mandating the integration of heavily black schools in urban Wilmington, Delaware with majority white schools in the city’s surrounding suburbs through busing. Abourezk, who at the time was one of most liberal members in Congress, hoped to stall the legislation within the Senate Judiciary Committee until that court ruling could be implemented.

“Clarence Mitchell of the NAACP approached me to ask if I would lead the fight against the bill in the Judiciary Committee,” Abourezk wrote in the book, which was reported by the Washington Free Beacon. “If I could hold up passage of the bill until the court’s ruling went into effect, the legislation would be nullified.”

Abourezk set his plan into motion when Sen. James Eastland (D-MS), who was then-chairman of the Judiciary Committee, scheduled a hearing on Biden’s bill.

“Eastland recognized me and I told the committee members to make themselves comfortable, because I intended to speak at length,” Abourezk recounted.

After the hearing, Biden, “with fire coming out of his eyes,” confronted Abourezk’ over his obstructionism.

Biden leaned over to me, fire coming out of his eyes, ‘Abourezk, you son of a bitch, if I ever vote for another one of your bills, it’ll be a cold day in hell.’ ‘Calm down, Joe,’ I told him, ‘You’re eventually gonna thank me for doing this.’ ‘Like hell I will you dirty bastard.’ Biden snorted, stomping out of the room.

Eastland, an ardent segregationist whose “civility” Biden recently praised, attempted to bring the legislation up for a vote on numerous other occasions, but to no avail from Abourezk.

Biden, who at the time was in his first term and considered an underdog for reelection in 1978, eventually warmed to Abourezk’s tactics.

Abourezk wrote:

A few days later, Biden came into the scheduled committee meeting, this time with a broad, friendly grin aimed directly at me. ‘Jesus, Abourezk, you were right,’ he said. ‘I am gonna thank you. You should see the Delaware newspapers—big front-page headlines saying, ‘Biden Battles Liberals in Washington.’ He was unabashedly elated. ‘They love me back home, how did you know this would happen?’

Although Biden came around to Abourezk’s tactics when they began to benefit him politically, he never shifted on his opposition to busing. In 1981, Biden told CNN he believed busing was not “constitutionally required” and that of all the options to desegregate schools it was the “least effective remedy.”