The public service broadcaster was found to have committed a "serious breach" of media regulations by omitting to mention that the voice of a programme about the Gaza situation was the child of a Hamas representative, according to British broadcasting authority Ofcom.
An inquiry by Ofcom into the programme Gaza: How to Survive a Warzone has determined that the programme was "materially misleading".
The BBC's director general had already issued an apology, saying there had been "a major oversight in relation to truthfulness".
Ofcom has instructed the corporation to broadcast a evening announcement about its conclusions.
"Given this constitutes a significant violation of our regulations, we are instructing the BBC to transmit a statement of our determinations against it on BBC Two at nine o'clock in the evening, with a date to be finalised," the regulator stated.
'Risk to Undermine Credibility'
The regulator's statement declared: "Our investigation found that the film's omission to reveal that the narrator's male guardian occupied a post in the Hamas-run administration was materially misleading.
"Consequently that the public did not have essential details which may have been extremely pertinent to their assessment of the voice and the content he presented.
"Confidence is at the heart of the bond between a media organization and its public, notably for a national broadcasting corporation such as the public broadcaster.
"This oversight had the risk to undermine the significantly high degrees of credibility that audiences would have invested in a factual film from the broadcaster about the Israel-Gaza war."
The documentary was pulled from iPlayer in last February after the boy's family links came to light, and in this past July an broadcaster's internal assessment determined it breached the organization's editorial guidelines on accuracy.
A BBC spokesperson stated: "The Ofcom ruling is in line with the findings of Peter Johnston's review, that there was a serious error in the documentary in relation to the broadcaster's journalistic policies on factual correctness, which aligns with clause 2.2 of Ofcom's Broadcasting Code.
"We issued an apology for this and we accept the authority's determination in full. We will comply with the sanction as soon as the schedule and wording are determined."
