The public service broadcaster committed a "major breach" of broadcasting rules by failing to disclose that the narrator of a film about Gaza was the offspring of a Hamas administrator, as determined by UK media regulator Ofcom.
An probe by Ofcom into Gaza: How to Survive a Warzone has found that the film was "substantially inaccurate".
The BBC's director general had earlier expressed regret, saying there had been "a significant failing in relation to accuracy".
Ofcom has ordered the corporation to broadcast a prime-time announcement about its findings.
"Since this amounts to a significant violation of our code, we are directing the corporation to air a statement of our conclusions against it on BBC Two at nine o'clock in the evening, with a timing to be confirmed," it said.
'Possibility to Undermine Trust'
The authority's statement declared: "The inquiry we conducted determined that the programme's lack of disclosure that the presenter's parent held a position in the Hamas-administered government was materially misleading.
"Consequently that the audience did not have vital facts which may have been very significant to their evaluation of the voice and the information he presented.
"Trust is at the center of the relationship between a television network and its viewers, notably for a public service broadcaster such as the public broadcaster.
"This failing had the possibility to erode the very considerable levels of trust that audiences would have invested in a factual film from the broadcaster about the conflict in Gaza."
The film was removed from the BBC's streaming service in last February after the boy's family links were revealed, and in the month of July an broadcaster's internal assessment determined it breached the corporation's journalistic standards on accuracy.
A BBC spokesperson said: "The authority's determination is in accordance 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 aligns with Rule 2.2 of Ofcom's Broadcasting Code.
"We issued an apology for this and we comply with Ofcom's decision in complete. We will adhere to the penalty as soon as the date and wording are confirmed."
