The public service broadcaster was found to have committed a "serious breach" of broadcasting rules by omitting to mention that the voice of a programme about the Gaza situation was the offspring of a Hamas representative, according to UK media regulator Ofcom.
An inquiry by Ofcom into the documentary titled Gaza: How to Survive a Warzone has found that the film was "substantially inaccurate".
The BBC's director general had previously apologised, stating there had been "a serious error in relation to truthfulness".
The regulator has instructed the corporation to air a prime-time announcement about its findings.
"Since this amounts to a serious breach of our regulations, we are directing the broadcaster to transmit a message of our conclusions against it on BBC Two at 21:00, with a schedule to be finalised," the statement read.
'Possibility to Erode Trust'
The regulator's report said: "Our investigation found that the documentary's omission to reveal that the narrator's father served in a role in the Hamas-run administration was materially misleading.
"This implied that the viewers did not have critical information which may have been extremely pertinent to their evaluation of the voice and the content he provided.
"Trust is at the center of the connection between a broadcaster and its public, especially for a state-funded media outlet such as the BBC.
"This error had the risk to erode the very considerable amounts of credibility that audiences would have placed in a documentary produced by the BBC about the Israel-Gaza war."
The programme was withdrawn from the online platform in February after the boy's familial connections were revealed, and in this past July an internal BBC review determined it breached the broadcaster's editorial guidelines on factual correctness.
A representative for the broadcaster commented: "The Ofcom ruling is in line with the findings of the internal assessment, that there was a major oversight in the programme in relation to the broadcaster's journalistic policies on accuracy, which aligns with Rule 2.2 of the authority's broadcasting regulations.
"We expressed regret for this and we comply with the authority's determination in its entirety. We will follow the penalty as soon as the date and wording are confirmed."
