The British broadcaster committed a "significant breach" of industry standards by not revealing that the narrator of a film about the Gaza conflict was the child of a Hamas official, as ruled by regulatory body Ofcom.
An inquiry by Ofcom into Gaza: How to Survive a Warzone has found that the programme was "substantially inaccurate".
The chief executive of the broadcaster had already issued an apology, saying there had been "a significant failing in relation to accuracy".
Ofcom has directed the BBC to broadcast a prime-time declaration about its decisions.
"Given this constitutes a major infringement of our code, we are directing the corporation to air a message of our determinations against it on the BBC's second channel at nine o'clock in the evening, with a date to be confirmed," the regulator stated.
'Potential to Damage Confidence'
The regulator's announcement declared: "Our probe concluded that the programme's failure to disclose that the narrator's male guardian served in a role in the Hamas-run authority was materially misleading.
"This implied that the viewers did not have critical information which may have been highly relevant to their evaluation of the narrator and the details he presented.
"Credibility is at the core of the relationship between a media organization and its viewers, notably for a public service broadcaster such as the public broadcaster.
"This oversight had the possibility to damage the exceptionally strong levels of credibility that viewers would have placed in a documentary produced by the BBC about the conflict in Gaza."
The documentary was withdrawn from iPlayer in the month of February after the boy's familial connections were revealed, and in July an internal BBC review determined it violated the broadcaster's content policies on accuracy.
A corporation official commented: "The authority's determination is in line with the findings of Peter Johnston's review, that there was a serious error in the film in relation to the corporation's content standards on accuracy, which aligns with clause 2.2 of the regulator's media standards.
"We have apologised for this and we agree with the regulator's ruling in full. We will follow the penalty as soon as the schedule and language are confirmed."
