The BBC engaged in a "significant breach" of broadcasting rules by omitting to mention that the voice of a film about the Gaza situation was the child of a Hamas administrator, as ruled by UK media regulator Ofcom.
An investigation by the broadcasting watchdog into the programme Gaza: How to Survive a Warzone has determined that the film was "significantly deceptive".
The chief executive of the broadcaster had earlier expressed regret, stating there had been "a significant failing in relation to truthfulness".
The authority has directed the corporation to transmit a prime-time announcement about its decisions.
"As this represents a significant violation of our rules, we are instructing the broadcaster to transmit a announcement of our findings against it on the BBC's second channel at nine o'clock in the evening, with a schedule to be finalised," it said.
'Risk to Undermine Trust'
The regulator's statement declared: "Our investigation found that the documentary's failure to disclose that the narrator's parent served in a post in the Hamas-run authority was materially misleading.
"It meant that the public did not have critical information which may have been highly relevant to their judgment of the narrator and the content he provided.
"Credibility is at the core of the relationship between a media organization and its viewers, especially for a state-funded media outlet such as the British Broadcasting Corporation.
"This error had the potential to damage the very considerable degrees of confidence that audiences would have put in a documentary produced by the BBC about the conflict in Gaza."
The documentary was removed from the BBC's streaming service in February after the presenter's familial connections emerged, and in this past July an broadcaster's internal assessment concluded it violated the broadcaster's editorial guidelines on truthfulness.
A corporation official said: "The Ofcom ruling is in accordance with the findings of the corporation's inquiry, that there was a significant failing in the film in relation to the broadcaster's journalistic policies on truthfulness, which reflects regulation 2.2 of the regulator's media standards.
"We issued an apology for this and we accept the authority's determination in complete. We will follow the penalty as soon as the timing and wording are confirmed."
