The BBC was found to have committed a "major breach" of industry standards by not revealing that the voice of a documentary about the Gaza conflict was the son of a Hamas administrator, according to UK media regulator Ofcom.
An inquiry by Ofcom into the programme Gaza: How to Survive a Warzone has found that the film was "materially misleading".
The chief executive of the broadcaster had already issued an apology, stating there had been "a serious error in relation to factual correctness".
Ofcom has directed the corporation to air a peak-time announcement about its conclusions.
"Since this amounts to a major infringement of our regulations, we are ordering the corporation to broadcast a message of our findings against it on the BBC's second channel at 21:00, with a timing to be determined," it said.
'Possibility to Undermine Confidence'
The regulator's statement declared: "Our investigation found that the documentary's lack of disclosure that the voice's male guardian served in a post in the Hamas-run administration was materially misleading.
"It meant that the viewers did not have vital facts which may have been very significant to their assessment of the presenter and the details he shared.
"Trust is at the center of the relationship between a television network and its audience, particularly for a public service broadcaster such as the BBC.
"This failing had the possibility to erode the significantly high amounts of confidence that the public would have put in a factual film from the broadcaster about the conflict in Gaza."
The film was pulled from iPlayer in the month of February after the boy's personal associations emerged, and in the month of July an internal BBC review found it breached the organization's editorial guidelines on truthfulness.
A BBC spokesperson said: "The regulator's decision is in line with the findings of the internal assessment, that there was a major oversight in the programme in relation to the broadcaster's journalistic policies on factual correctness, which reflects Rule 2.2 of Ofcom's Broadcasting Code.
"We expressed regret for this and we accept the regulator's ruling in its entirety. We will comply with the sanction as soon as the timing and wording are finalised."
