Senator Bernie Sanders has denied that he sent a message of support to Labour leader Jeremy Corbyn.
Mr Corbyn told supporters at a phone bank event on Monday that the Jewish senator, who lost out to Hillary Clinton in the race for the Democratic Party nomination, had favourably compared the two politicians.
A spokesman for Mr Corbyn later admitted that this was a mistake.
Speaking in Walthamstow, east London, as part of his leadership campaign, the Labour leader said: “We had a message yesterday from Bernie Sanders, saying that they condemned him because he wasn't electable,” the Press Association reported.
Mr Corbyn added: “And he said the reason they condemned him was because he was electable. And he represented a threat to the establishment within the USA.
“So I think you can see the parallels that are going on there.”
But a spokesman for Senator Sanders told the JC that the Vermont representative “doesn't intend to get involved in British politics but admires Mr Corbyn and wishes him well".
In response, a spokesman for Mr Corbyn said: “Jeremy was misinformed by an aide, who had wrongly been led to believe this was the case.”