The public service broadcaster engaged in a "major breach" of industry standards by not revealing that the narrator of a film about the Gaza situation was the offspring of a Hamas official, as determined by UK media regulator Ofcom.
An investigation by Ofcom into Gaza: How to Survive a Warzone has concluded that the programme was "materially misleading".
The BBC's director general had earlier expressed regret, stating there had been "a major oversight in relation to truthfulness".
Ofcom has directed the BBC to transmit a evening statement about its conclusions.
"As this represents a serious breach of our rules, we are instructing the corporation to broadcast a statement of our findings against it on the BBC's second channel at nine o'clock in the evening, with a schedule to be confirmed," it said.
'Potential to Undermine Credibility'
The authority's announcement stated: "Our probe concluded that the documentary's failure to disclose that the presenter's parent occupied a position in the Hamas-run authority was materially misleading.
"This implied that the audience did not have critical information which may have been extremely pertinent to their judgment of the voice and the content he provided.
"Confidence is at the heart of the connection between a broadcaster and its viewers, notably for a national broadcasting corporation such as the BBC.
"This error had the potential to erode the exceptionally strong degrees of confidence that viewers would have invested in a documentary produced by the BBC about the Gaza conflict."
The film was pulled from the online platform in last February after the boy's personal associations came to light, and in July an corporation's own inquiry concluded it breached the organization's journalistic standards on truthfulness.
A corporation official said: "The authority's determination is in accordance with the results of Peter Johnston's review, that there was a serious error in the programme in relation to the BBC's Editorial Guidelines on truthfulness, which aligns with Rule 2.2 of the authority's broadcasting regulations.
"We have apologised for this and we agree with the regulator's ruling in its entirety. We will follow the directive as soon as the date and wording are finalised."
