The BBC engaged in a "significant breach" of broadcasting rules by omitting to mention that the narrator of a documentary about the Gaza situation was the offspring of a Hamas official, as determined by UK media regulator Ofcom.
An inquiry by Ofcom into the programme Gaza: How to Survive a Warzone has concluded that the programme was "substantially inaccurate".
The chief executive of the broadcaster had already issued an apology, stating there had been "a major oversight in relation to factual correctness".
The authority has instructed the corporation to air a peak-time announcement about its conclusions.
"As this represents a serious breach of our code, we are instructing the broadcaster to transmit a message of our conclusions against it on BBC Two at 9pm, with a timing to be determined," it said.
'Possibility to Erode Trust'
The authority's report declared: "Our investigation concluded that the film's failure to disclose that the narrator's male guardian occupied a role in the Hamas-controlled government was significantly deceptive.
"It meant that the public did not have essential details which may have been extremely pertinent to their assessment of the voice and the information he presented.
"Confidence is at the heart of the bond between a media organization and its audience, notably for a public service broadcaster such as the BBC.
"This oversight had the risk to damage the significantly high degrees of confidence that the public would have invested in a BBC factual programme about the Gaza conflict."
The programme was pulled from the online platform in February after the boy's family links emerged, and in July an broadcaster's internal assessment found it violated the corporation's editorial guidelines on truthfulness.
A BBC spokesperson stated: "The regulator's decision is in accordance with the conclusions of the internal assessment, that there was a significant failing in the film in relation to the broadcaster's journalistic policies on accuracy, which aligns with clause 2.2 of the regulator's media standards.
"We expressed regret for this and we accept the regulator's ruling in full. We will follow the sanction as soon as the schedule and wording are finalised."
