The British broadcaster committed a "major breach" of media regulations by not revealing that the presenter of a programme about the Gaza conflict was the son of a Hamas administrator, as ruled by British broadcasting authority Ofcom.
An inquiry by the broadcasting watchdog into Gaza: How to Survive a Warzone has concluded that the documentary was "substantially inaccurate".
The BBC's director general had already issued an apology, saying there had been "a serious error in relation to factual correctness".
The regulator has instructed the corporation to transmit a evening declaration about its findings.
"Since this amounts to a serious breach of our code, we are ordering the broadcaster to transmit a announcement of our conclusions against it on the BBC's second channel at 21:00, with a timing to be confirmed," it said.
'Possibility to Undermine Credibility'
The regulator's statement stated: "Our investigation found that the documentary's failure to disclose that the presenter's father occupied a post in the Hamas-run administration was substantially inaccurate.
"It meant that the public did not have vital facts which may have been highly relevant to their judgment of the presenter and the content he shared.
"Credibility is at the core of the bond between a media organization and its audience, particularly for a public service broadcaster such as the British Broadcasting Corporation.
"This oversight had the possibility to erode the significantly high amounts of confidence that viewers would have put in a documentary produced by the BBC about the conflict in Gaza."
The programme was withdrawn from the online platform in last February after the presenter's family links emerged, and in July an corporation's own inquiry determined it infringed the broadcaster's content policies on accuracy.
A representative for the broadcaster commented: "The authority's determination is in accordance with the findings of Peter Johnston's review, that there was a serious error in the film in relation to the corporation's content standards on truthfulness, which aligns with clause 2.2 of the regulator's media standards.
"We have apologised for this and we accept Ofcom's decision in full. We will adhere to the sanction as soon as the date and wording are determined."
