The BBC committed a "serious breach" of industry standards by not revealing that the narrator of a film about the Gaza situation was the son of a Hamas official, according to regulatory body Ofcom.
An inquiry by the broadcasting watchdog into the programme Gaza: How to Survive a Warzone has found that the documentary was "significantly deceptive".
The chief executive of the broadcaster had earlier expressed regret, saying there had been "a major oversight in relation to factual correctness".
The regulator has ordered the BBC to transmit a peak-time announcement about its conclusions.
"Given this constitutes a serious breach of our rules, we are directing the corporation to broadcast a statement of our findings against it on BBC2 at 21:00, with a schedule to be confirmed," the regulator stated.
'Possibility to Erode Trust'
The regulator's report stated: "The inquiry we conducted concluded that the film's lack of disclosure that the voice's male guardian served in a position in the Hamas-run administration was materially misleading.
"Consequently that the audience did not have critical information which may have been very significant to their evaluation of the voice and the details he shared.
"Confidence is at the core of the relationship between a media organization and its viewers, especially for a national broadcasting corporation such as the British Broadcasting Corporation.
"This oversight had the possibility to erode the exceptionally strong levels of credibility that the public would have invested in a factual film from the broadcaster about the Israel-Gaza war."
The film was withdrawn from iPlayer in February after the boy's family links came to light, and in July an internal BBC review found it violated the organization's editorial guidelines on accuracy.
A corporation official stated: "The Ofcom ruling is in line with the conclusions of the corporation's inquiry, that there was a serious error in the programme in relation to the BBC's Editorial Guidelines on accuracy, which corresponds to Rule 2.2 of the authority's broadcasting regulations.
"We have apologised for this and we comply with the authority's determination in its entirety. We will follow the sanction as soon as the timing and language are finalised."
