The British broadcaster engaged in a "significant breach" of industry standards by omitting to mention that the voice of a programme about Gaza was the offspring of a Hamas official, as ruled by British broadcasting authority Ofcom.
An inquiry by Ofcom into the programme Gaza: How to Survive a Warzone has determined that the film was "materially misleading".
The chief executive of the broadcaster had earlier expressed regret, noting there had been "a major oversight in relation to truthfulness".
The regulator has directed the broadcaster to transmit a peak-time declaration about its decisions.
"Given this constitutes a major infringement of our code, we are instructing the corporation to broadcast a statement of our conclusions against it on BBC Two at 21:00, with a timing to be determined," it said.
'Risk to Erode Credibility'
The regulator's statement stated: "Our investigation found that the programme's failure to disclose that the narrator's male guardian held a role in the Hamas-administered administration was substantially inaccurate.
"This implied that the public did not have critical information which may have been highly relevant to their judgment of the presenter and the details he provided.
"Credibility is at the heart of the bond between a broadcaster and its viewers, notably for a state-funded media outlet such as the British Broadcasting Corporation.
"This error had the possibility to undermine the exceptionally strong levels of trust that audiences would have put in a factual film from the broadcaster about the Israel-Gaza war."
The documentary was withdrawn from iPlayer in last February after the boy's family links were revealed, and in July an corporation's own inquiry concluded it infringed the corporation's editorial guidelines on accuracy.
A representative for the broadcaster commented: "The authority's determination is in line with the results of Peter Johnston's review, that there was a major oversight in the documentary in relation to the broadcaster's journalistic policies on accuracy, which corresponds to clause 2.2 of the authority's broadcasting regulations.
"We issued an apology for this and we agree with Ofcom's decision in full. We will follow the sanction as soon as the timing and language are confirmed."
