The BBC was found to have committed a "significant breach" of broadcasting rules by failing to disclose that the voice of a programme about the Gaza conflict was the child of a Hamas representative, as ruled by regulatory body Ofcom.
An probe by the media regulator into Gaza: How to Survive a Warzone has concluded that the film was "significantly deceptive".
The head of the BBC had previously apologised, noting there had been "a major oversight in relation to truthfulness".
Ofcom has directed the corporation to broadcast a evening declaration about its findings.
"As this represents a serious breach of our code, we are instructing the broadcaster to transmit a statement of our determinations against it on BBC2 at 9pm, with a timing to be determined," it said.
'Possibility to Damage Confidence'
The regulator's report said: "Our probe found that the documentary's omission to reveal that the narrator's father occupied a role in the Hamas-administered authority was materially misleading.
"It meant that the public did not have critical information which may have been extremely pertinent to their assessment of the presenter and the details he shared.
"Confidence is at the center of the relationship between a television network and its audience, particularly for a national broadcasting corporation such as the British Broadcasting Corporation.
"This failing had the potential to undermine the significantly high degrees of credibility that audiences would have put in a factual film from the broadcaster about the Gaza conflict."
The documentary was pulled from the online platform in February after the boy's familial connections emerged, and in July an internal BBC review found it breached the organization's editorial guidelines on accuracy.
A representative for the broadcaster stated: "The regulator's decision is in accordance with the conclusions of Peter Johnston's review, that there was a serious error in the documentary in relation to the broadcaster's journalistic policies on factual correctness, which reflects regulation 2.2 of Ofcom's Broadcasting Code.
"We expressed regret for this and we agree with the authority's determination in complete. We will follow the penalty as soon as the schedule and language are determined."
