The public service broadcaster committed a "major breach" of industry standards by failing to disclose that the presenter of a programme about Gaza was the son of a Hamas official, as ruled by UK media regulator Ofcom.
An probe by the broadcasting watchdog into the programme Gaza: How to Survive a Warzone has found that the film was "materially misleading".
The BBC's director general had earlier expressed regret, stating there had been "a serious error in relation to accuracy".
Ofcom has instructed the broadcaster to broadcast a prime-time announcement about its conclusions.
"Given this constitutes a major infringement of our regulations, we are ordering the corporation to broadcast a statement of our conclusions against it on the BBC's second channel at nine o'clock in the evening, with a schedule to be confirmed," the statement read.
'Possibility to Erode Trust'
The authority's report stated: "The inquiry we conducted concluded that the documentary's omission to reveal that the voice's male guardian occupied a position in the Hamas-controlled authority was substantially inaccurate.
"It meant that the viewers did not have vital facts which may have been extremely pertinent to their evaluation of the voice and the content he provided.
"Credibility is at the center of the connection between a media organization and its viewers, especially for a state-funded media outlet such as the British Broadcasting Corporation.
"This oversight had the potential to undermine the exceptionally strong levels of trust that the public would have put in a factual film from the broadcaster about the Israel-Gaza war."
The programme was withdrawn from the BBC's streaming service in last February after the narrator's personal associations emerged, and in this past July an corporation's own inquiry found it breached the corporation's editorial guidelines on factual correctness.
A representative for the broadcaster stated: "The regulator's decision is in line with the findings of Peter Johnston's review, that there was a major oversight in the film in relation to the BBC's Editorial Guidelines on accuracy, which reflects regulation 2.2 of Ofcom's Broadcasting Code.
"We issued an apology for this and we accept Ofcom's decision in complete. We will follow the sanction as soon as the date and wording are determined."
