The BBC committed a "major breach" of media regulations by failing to disclose that the narrator of a programme about Gaza was the offspring of a Hamas official, as ruled by British broadcasting authority Ofcom.
An inquiry by the broadcasting watchdog into the programme Gaza: How to Survive a Warzone has concluded that the film was "significantly deceptive".
The BBC's director general had previously apologised, stating there had been "a major oversight in relation to accuracy".
The regulator has instructed the corporation to air a peak-time announcement about its conclusions.
"Since this amounts to a major infringement of our rules, we are instructing the BBC to transmit a announcement of our conclusions against it on BBC2 at nine o'clock in the evening, with a schedule to be determined," the regulator stated.
'Possibility to Erode Confidence'
The authority's statement stated: "The inquiry we conducted determined that the documentary's omission to reveal that the narrator's father held a post in the Hamas-administered authority was materially misleading.
"This implied that the public did not have vital facts which may have been very significant to their judgment of the narrator and the information he provided.
"Confidence is at the heart of the bond between a broadcaster and its public, particularly for a public service broadcaster such as the British Broadcasting Corporation.
"This failing had the risk to erode the exceptionally strong degrees of confidence that viewers would have invested in a BBC factual programme about the Gaza conflict."
The documentary was withdrawn from the BBC's streaming service in last February after the presenter's personal associations came to light, and in the month of July an corporation's own inquiry determined it infringed the corporation's journalistic standards on accuracy.
A representative for the broadcaster commented: "The Ofcom ruling is in agreement with the findings of the internal assessment, that there was a significant failing in the documentary in relation to the corporation's content standards on factual correctness, which aligns with clause 2.2 of Ofcom's Broadcasting Code.
"We have apologised for this and we accept Ofcom's decision in full. We will comply with the penalty as soon as the date and wording are determined."
