The public service broadcaster committed a "significant breach" of media regulations by failing to disclose that the voice of a film about the Gaza situation was the child of a Hamas administrator, according to regulatory body Ofcom.
An probe by Ofcom into the programme Gaza: How to Survive a Warzone has found that the documentary was "significantly deceptive".
The chief executive of the broadcaster had previously apologised, stating there had been "a major oversight in relation to truthfulness".
Ofcom has instructed the BBC to air a peak-time announcement about its conclusions.
"Given this constitutes a major infringement of our code, we are directing the corporation to transmit a announcement of our conclusions against it on the BBC's second channel at nine o'clock in the evening, with a date to be finalised," the statement read.
'Risk to Undermine Credibility'
The watchdog's statement said: "Our investigation concluded that the film's lack of disclosure that the narrator's parent held a position in the Hamas-controlled government was substantially inaccurate.
"It meant that the public did not have vital facts which may have been extremely pertinent to their assessment of the narrator and the details he provided.
"Credibility is at the heart of the connection between a media organization and its public, especially for a national broadcasting corporation such as the British Broadcasting Corporation.
"This failing had the potential to damage the very considerable levels of credibility that the public would have placed in a documentary produced by the BBC about the conflict in Gaza."
The film was pulled from the online platform in last February after the presenter's personal associations came to light, and in July an corporation's own inquiry found it violated the broadcaster's journalistic standards on accuracy.
A corporation official said: "The authority's determination is in line with the findings of the internal assessment, that there was a major oversight in the documentary in relation to the corporation's content standards on truthfulness, which reflects Rule 2.2 of the authority's broadcasting regulations.
"We issued an apology for this and we comply with Ofcom's decision in its entirety. We will follow the sanction as soon as the schedule and language are determined."
