Joe Biden appeared to confuse French President Emmanuel Macron with his predecessor Francois Mitterand, who died in 1996.
In a campaign speech in Las Vegas, the US president was remarking on how the leaders of France and Germany reacted when they saw him at a G7 summit after the January 6 riots at the Capitol.
Recounting their exchange shortly after he was elected, he also referred to Mitterand as “from Germany”, before quickly correcting he was from France.
“I sat down and I said ‘America’s back’ and Mitterand from Germany, I mean from France, looked at me and said how long are you back for,” he said.
Mitterand served as president of France from 1981 to 1995.
Biden added that then-German Chancellor Angela Merkel asked him how he would react if he saw thousands break through the House of Commons in the UK to stop the election of a prime minister.
“I never thought about it from that perspective,” he said.
“What would we say if that happened in another democracy around the world?”
His comments, made on Monday night, came less than a day before he appeared to freeze while updating reporters on a potential hostage deal between Israel and Hamas.
“There is some movement and I don’t want to… choose my words,” he said on Tuesday, speaking slowly.
“There is some movement, there has been a response from the… there has been a response from the opposition but, yes, I’m sorry, from Hamas, but it seems to be a little over the top.”
Latest mishap
It is the latest in a series of apparent gaffes made by the president, who confused Taylor Swift and Britney Spears in November while pardoning turkeys in a Thanksgiving ceremony.
While in Ireland in April last year, he referred to famous rugby player Rob Kearney, who was part of the Irish team that beat New Zealand – known as the All Blacks – for the first time in 2016.
Kearney was “a hell of a rugby player”, said Biden, before unfortunately adding he “beat the Black and Tans”, the reviled British paramilitary force that brutally repressed opponents of British rule during the Irish War of Independence.
In September, Mr Biden mistakenly praised the “Congressional Black Caucus” while addressing the Congressional Hispanic Caucus at the group’s annual gala in Washington DC.
In June, the president made a comment about Russian leader Vladimir Putin’s “war in Iraq”, which led to him being mocked online.
Mr Biden is already the oldest president the US has ever had, ahead of Ronald Reagan, who was 77 when his time in office ended.
Should he win the presidency, he could be in the White House until the age of 85.