At the end of a two-day visit to Israel, Mr Biden not only risked upsetting his hosts but also made deeply insensitive remarks about the UK's relationship with Ireland.
Announcing £84million of funding for Palestinian hospitals, the 79-year-old said: “My background and the background of my family is Irish American, and we have a long history of — not fundamentally unlike the Palestinian people — with Great Britain and their attitude towards Irish-Catholics over the years, for 400 years."
He then quoted a poem by Seamus Heaney that says sometimes “justice rises up/ And hope and history rhyme”.
He added: “Palestinians and Israelis deserve equal measure of freedom, security, prosperity and dignity.
"And access to healthcare, when you need it, is essential to living a life of dignity.”
While there was no immediate official British reaction, Sir Paul Lever – a former British ambassador to Germany – tweeted: “President Biden has compared Israel’s treatment of the Palestinians with Britain’s treatment of Irish Catholics.
"He could also have mentioned, but didn’t, his own country’s treatment of black and native Americans.”
It was not the only eyebrow-raising moment on the Israel tour, as he began the trip by talking of a "bone-deep connection" between the US and Israel while declaring: "You need not be a Jew to be a Zionist."
The timing of Mr Biden's gaffe make its ramifications all the more significant, given the current tensions over the Northern Ireland Protocol.
The White House has already warned Britain that making alterations to the Protocol may impact the Good Friday agreement.
It is not the first time Mr Biden has stressed his Irish heritage, either.
In 2020, he turned down a request for comment from a British journalist by simply saying: "I'm Irish."
And earlier this year, he risked offending the Irish themselves with an ill-conceived joke on St Patrick's Day.
He said: “I may be Irish but I’m not stupid.”
US President Joe Biden EVELYN HOCKSTEIN
Mr Biden was on a two-day tour of Israel EVELYN HOCKSTEIN