The Senate minority leader, Mitch McConnell, said on Monday it was “highly unlikely” he would allow Joe Biden to fill a supreme court vacancy arising in 2024, the year of the next presidential election, if Republicans regained control of the chamber. “I think it’s highly unlikely – in fact, no, I don’t think either party, if it were different from the president, would confirm a supreme court nominee in the middle of an election,” McConnell told Hugh Hewitt, a conservative radio host. McConnell blocked Barack Obama from filling a vacancy in 2016, denying Merrick Garland, now attorney general, even a hearing after he was nominated to fill the seat vacated by the death of Antonin Scalia. McConnell said that was because no new justice should be seated in an election year – a position he reversed with alacrity in 2020, on the death of Ruth Bader Ginsburg two months before polling day. Ginsburg, a liberal lion, was replaced by the conservative Amy Coney Barrett, tipping the court 6-3 to the right. Major cases are coming up on abortion rights, gun control, affirmative action and more. McConnell claimed then, and repeated to Hewitt, that no new justice should be seated in an election year when the White House and the Senate are controlled by different parties. “I think in the middle of a presidential election,” McConnell said, “if you have a Senate of the opposite party of the president, you have to go back to the 1880s to find the last time a vacancy was filled. “So I think it’s highly unlikely. In fact, no, I don’t think either party if it controlled, if it were different from the president would confirm a supreme court nominee in the middle of an election. What was different in 2020 was we were of the same party as the president. And that’s why we went ahead with it.” Asked what would happen if a vacancy arose in 2023 with Republicans in control of the Senate, McConnell said: “We’ll have to wait and see what happens.” He also said keeping Scalia’s seat open – to be filled under Donald Trump by Neil Gorsuch – “is the single most consequential thing I’ve done in my time as majority leader of the Senate”. McConnell’s hardball tactics have contributed to his status as a hate figure among progressives. On Monday, much online reaction to his remarks focused on beseeching Stephen Breyer, a liberal and at 82 the oldest justice on the current court, to retire while Biden is in the White House and Democrats hold the Senate. Rick Hasen, a professor of law and political science at the University of California, Irvine, said: “Exactly as I wrote last week. McConnell will NOT fill a Breyer seat if he’s majority leader, even if he has to wait two years with the seat open.” Jeet Heer, a columnist for the Nation, wrote: “Can someone send this to USA supreme court justice Stephen Breyer. Thanks!” The conservative hold on the court was strengthened in 2018 when Anthony Kennedy, often a swing vote on civil rights issues, stepped down and was replaced by Brett Kavanaugh, once an official in the White House of George W Bush. Kavanaugh faced and denied allegations of sexual assault during a stormy confirmation but McConnell said he was “stronger than mule piss” in support and the process was duly completed. Breyer, appointed by Bill Clinton in 1994, has shown little inclination to follow Kennedy’s example and step aside for a younger justice. Last month, he angered some on the left by telling high school and middle school students the key to working with conservatives was to talk to them more. Among progressives, support is growing for countering conservative dominance of the court by increasing the number of justices. Republicans are stringently opposed. McConnell told Hewitt he wanted to give Breyer “a shout out, though, because he joined what Justice Ginsburg said in 2019, that nine is the right number for the supreme court, and I admire him for that. I think even the liberal justices on the supreme court have made it clear that court packing is a terrible idea.” The number of justices on the court is not fixed in the constitution.