The public service broadcaster engaged in a "serious breach" of broadcasting rules by failing to disclose that the narrator of a programme about Gaza was the child of a Hamas representative, according to regulatory body Ofcom.
An probe by the broadcasting watchdog into the documentary titled Gaza: How to Survive a Warzone has found that the film was "significantly deceptive".
The chief executive of the broadcaster had already issued an apology, saying there had been "a serious error in relation to accuracy".
Ofcom has ordered the BBC to transmit a evening announcement about its findings.
"As this represents a significant violation of our code, we are directing the broadcaster to air a message of our determinations against it on BBC Two at 21:00, with a timing to be confirmed," the statement read.
'Possibility to Damage Confidence'
The watchdog's report said: "Our probe determined that the programme's omission to reveal that the voice's parent held a position in the Hamas-administered government was significantly deceptive.
"Consequently that the public did not have critical information which may have been very significant to their judgment of the narrator and the information he presented.
"Credibility is at the core of the relationship between a broadcaster and its audience, particularly for a national broadcasting corporation such as the public broadcaster.
"This failing had the risk to erode the exceptionally strong levels of credibility that audiences would have put in a documentary produced by the BBC about the Israel-Gaza war."
The film was removed from the BBC's streaming service in the month of February after the boy's personal associations emerged, and in July an internal BBC review found it breached the corporation's editorial guidelines on accuracy.
A BBC spokesperson said: "The regulator's decision is in accordance with the findings of Peter Johnston's review, that there was a significant failing in the film in relation to the BBC's Editorial Guidelines on accuracy, which reflects regulation 2.2 of the authority's broadcasting regulations.
"We issued an apology for this and we accept the authority's determination in full. We will follow the directive as soon as the schedule and wording are confirmed."
