The BBC engaged in a "serious breach" of broadcasting rules by failing to disclose that the voice of a documentary about the Gaza conflict was the child of a Hamas administrator, as ruled by regulatory body Ofcom.
An inquiry by the broadcasting watchdog into Gaza: How to Survive a Warzone has concluded that the documentary was "significantly deceptive".
The head of the BBC had already issued an apology, stating there had been "a significant failing in relation to factual correctness".
Ofcom has ordered the broadcaster to broadcast a evening announcement about its findings.
"Since this amounts to a significant violation of our regulations, we are instructing the broadcaster to air a announcement of our conclusions against it on the BBC's second channel at nine o'clock in the evening, with a schedule to be confirmed," it said.
'Risk to Damage Confidence'
The authority's announcement stated: "Our probe concluded that the documentary's omission to reveal that the narrator's male guardian served in a role in the Hamas-run government was materially misleading.
"Consequently that the public did not have essential details which may have been extremely pertinent to their assessment of the narrator and the information he provided.
"Credibility is at the core of the relationship between a broadcaster and its public, especially for a state-funded media outlet such as the British Broadcasting Corporation.
"This failing had the possibility to undermine the significantly high levels of trust that the public would have put in a factual film from the broadcaster about the conflict in Gaza."
The documentary was pulled from iPlayer in February after the boy's familial connections came to light, and in this past July an internal BBC review determined it infringed the broadcaster's editorial guidelines on factual correctness.
A corporation official commented: "The regulator's decision is in agreement with the findings of Peter Johnston's review, that there was a significant failing in the film in relation to the corporation's content standards on accuracy, which reflects Rule 2.2 of the authority's broadcasting regulations.
"We have apologised for this and we accept the authority's determination in full. We will comply with the sanction as soon as the schedule and language are finalised."
