George Galloway's radio show, in which he ranted that allegations of antisemitism against Jeremy Corbyn were "a giant Goebellian lie", breached Ofcom rules around impartiality, the watchdog has found.
Ofcom accused TalkRadio of "serious" breaches of its code with the broadcast of Mr Galloway's show and threatened sanctions, depending on how the station responds.
The show went out in July last year after three Jewish newspapers, including the JC, warned a Labour Government under Mr Corbyn posed a "existential threat" to British Jews.
During the broadcast, Mr Galloway said claims against Mr Corbyn were "a crazed, unhinged assault by the agents of the powerful".
He interviewed Graham Bash, from the hard-left Labour Briefing, who called allegations of Labour Jew-hate "an attack by the pro-Israeli lobby who are trying to silence criticism".
Mr Galloway read out many texts from listeners agreeing with him but mocked someone who had sent a text disagreeing with him, calling the sender a "gutless coward" and mocking misspellings in the text.
The broadcasting watchdog said TalkRadio had "failed to include and give due weight to an appropriately wide range of significant viewpoints in relation to the relevant matter of major political controversy and major matter relating to current public policy dealt with in the programme".
Ofcom also reprimanded TalkRadio for a broadcast by Mr Galloway on August 6.
During that, he said of Labour deputy leader Tom Watson: "You are the one who has disappeared into a vortex, a vortex paid for by the Israel lobby in Britain."
He also spoke to Glyn Secker, secretary of the fringe, pro-Corbyn Jewish Voice For Labour, who said: "It's a campaign against Corbyn. And it’s a campaign against free speech on Israel... they won't be satisfied until they have Corbyn's head."
In response to Ofcom's initial findings against him, Mr Galloway said it was a bid "to silence the only presenter on British radio and television who is prepared to defend the leader of Her Majesty’s Opposition in the teeth of industrialised prejudice and legalised lying when it comes to Mr Corbyn".
He said Ofcom's findings showed "just how deeply prejudiced [it is] against the Palestinian people, how abjectly [Ofcom] toes the Israel-lobby line, and the contempt [Ofcom] implicitly feels for the many millions of British taxpayers whose money [Ofcom is] abusing who agree with me on all the issues covered by [Ofcom’s] investigation”.
A TalkRadio spokesperson said: "You expect robust opinions from George Galloway but we accept that on this occasion he crossed the line.
“As a station we understand the need for dissenting voices with a range of counter-opinions.”
Ofcom said it would consider TalkRadio's response to its findings before deciding what steps to take.
