The British broadcaster committed a "significant breach" of industry standards by failing to disclose that the narrator of a film about the Gaza situation was the son of a Hamas administrator, according to UK media regulator Ofcom.
An inquiry by Ofcom into Gaza: How to Survive a Warzone has found that the documentary was "substantially inaccurate".
The chief executive of the broadcaster had already issued an apology, saying there had been "a serious error in relation to factual correctness".
The regulator has ordered the BBC to broadcast a evening announcement about its decisions.
"As this represents a serious breach of our regulations, we are instructing the broadcaster to air a announcement of our findings against it on BBC2 at 21:00, with a timing to be confirmed," the statement read.
'Potential to Erode Confidence'
The authority's announcement stated: "Our probe determined that the programme's failure to disclose that the presenter's father occupied a post in the Hamas-run authority was significantly deceptive.
"This implied that the viewers did not have critical information which may have been very significant to their judgment of the voice and the details he provided.
"Trust is at the heart of the bond between a media organization and its audience, particularly for a state-funded media outlet such as the BBC.
"This oversight had the risk to undermine the significantly high degrees of credibility that viewers would have placed in a BBC factual programme about the Gaza conflict."
The film was withdrawn from iPlayer in the month of February after the boy's personal associations emerged, and in July an corporation's own inquiry concluded it infringed the broadcaster's editorial guidelines on accuracy.
A corporation official said: "The Ofcom ruling is in agreement with the results of the corporation's inquiry, that there was a major oversight in the programme in relation to the BBC's Editorial Guidelines on factual correctness, which reflects Rule 2.2 of the regulator's media standards.
"We issued an apology for this and we accept the authority's determination in full. We will comply with the sanction as soon as the date and wording are confirmed."
