The BBC committed a "major breach" of media regulations by not revealing that the voice of a film about the Gaza situation was the offspring of a Hamas administrator, as ruled by UK media regulator Ofcom.
An investigation by Ofcom 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 accuracy".
The authority has instructed the BBC to broadcast a prime-time statement about its conclusions.
"As this represents a serious breach of our rules, we are directing the BBC to air a announcement of our findings against it on BBC Two at 9pm, with a schedule to be finalised," the regulator stated.
'Possibility to Undermine Trust'
The regulator's report declared: "Our probe concluded that the documentary's failure to disclose that the voice's parent held a position in the Hamas-run administration was materially misleading.
"This implied that the audience did not have critical information which may have been extremely pertinent to their judgment of the narrator and the content he shared.
"Trust is at the heart of the bond between a broadcaster and its public, especially for a public service broadcaster such as the public broadcaster.
"This oversight had the potential to undermine the very considerable degrees of confidence that audiences would have placed in a factual film from the broadcaster about the conflict in Gaza."
The film was pulled from iPlayer in last February after the narrator's personal associations emerged, and in July an broadcaster's internal assessment determined it breached the organization's editorial guidelines on factual correctness.
A representative for the broadcaster stated: "The Ofcom ruling is in accordance with the conclusions of the corporation's inquiry, that there was a significant failing in the film in relation to the BBC's Editorial Guidelines on accuracy, which aligns with clause 2.2 of Ofcom's Broadcasting Code.
"We expressed regret for this and we agree with the regulator's ruling in full. We will comply with the directive as soon as the date and wording are confirmed."
