The BBC engaged in a "serious breach" of industry standards by failing to disclose that the narrator of a programme about the Gaza conflict was the offspring of a Hamas official, according to UK media regulator Ofcom.
An inquiry by the media regulator into Gaza: How to Survive a Warzone has found that the documentary was "substantially inaccurate".
The head of the BBC had already issued an apology, noting there had been "a significant failing in relation to truthfulness".
The regulator has instructed the broadcaster to air a prime-time declaration about its findings.
"Given this constitutes a serious breach of our regulations, we are ordering the BBC to transmit a statement of our findings against it on BBC Two at nine o'clock in the evening, with a timing to be confirmed," it said.
'Risk to Erode Credibility'
The authority's report stated: "Our investigation determined that the film's failure to disclose that the narrator's parent occupied a role in the Hamas-controlled administration was materially misleading.
"It meant that the audience did not have vital facts which may have been extremely pertinent to their judgment of the narrator and the details he provided.
"Confidence is at the heart of the bond between a broadcaster and its viewers, especially for a national broadcasting corporation such as the BBC.
"This failing had the risk to damage the significantly high degrees of trust that the public would have invested in a BBC factual programme about the Gaza conflict."
The documentary was pulled from the BBC's streaming service in the month of February after the presenter's familial connections emerged, and in July an broadcaster's internal assessment concluded it breached the organization's content policies on accuracy.
A BBC spokesperson commented: "The Ofcom ruling is in agreement with the conclusions of Peter Johnston's review, that there was a major oversight in the documentary in relation to the broadcaster's journalistic policies on truthfulness, which aligns with clause 2.2 of the authority's broadcasting regulations.
"We have apologised for this and we accept the regulator's ruling in full. We will adhere to the directive as soon as the date and wording are determined."
