The British broadcaster engaged in a "serious breach" of industry standards by not revealing that the presenter of a programme about Gaza was the child of a Hamas representative, as determined by regulatory body Ofcom.
An investigation by Ofcom into Gaza: How to Survive a Warzone has determined that the film was "significantly deceptive".
The chief executive of the broadcaster had earlier expressed regret, noting there had been "a serious error in relation to truthfulness".
The authority has directed the corporation to air a evening declaration about its findings.
"Since this amounts to a significant violation of our rules, we are directing the corporation to air a announcement of our conclusions against it on the BBC's second channel at 21:00, with a timing to be determined," the statement read.
'Risk to Undermine Credibility'
The authority's report said: "Our probe determined that the documentary's failure to disclose that the voice's male guardian held a role in the Hamas-administered government was substantially inaccurate.
"This implied that the public did not have critical information which may have been highly relevant to their judgment of the voice and the details he provided.
"Credibility is at the core of the bond between a media organization and its audience, notably for a national broadcasting corporation such as the public broadcaster.
"This failing had the potential to erode the very considerable levels of confidence that the public would have placed in a BBC factual programme about the Israel-Gaza war."
The programme was withdrawn from iPlayer in last February after the boy's familial connections came to light, and in this past July an broadcaster's internal assessment determined it breached the corporation's content policies on truthfulness.
A corporation official commented: "The Ofcom ruling is in line with the conclusions of the corporation's inquiry, that there was a significant failing in the film in relation to the corporation's content standards on accuracy, which aligns with regulation 2.2 of the authority's broadcasting regulations.
"We issued an apology for this and we comply with Ofcom's decision in its entirety. We will comply with the sanction as soon as the timing and language are finalised."
