The public service broadcaster committed a "serious breach" of media regulations by not revealing that the narrator of a film about the Gaza conflict was the son of a Hamas administrator, as ruled by regulatory body Ofcom.
An probe by Ofcom into the programme Gaza: How to Survive a Warzone has determined that the documentary was "significantly deceptive".
The BBC's director general had previously apologised, saying there had been "a significant failing in relation to truthfulness".
The authority has ordered the broadcaster to transmit a prime-time declaration about its conclusions.
"Given this constitutes a major infringement of our regulations, we are directing the corporation to air a statement of our findings against it on BBC Two at nine o'clock in the evening, with a date to be finalised," it said.
'Possibility to Undermine Credibility'
The authority's announcement declared: "Our investigation determined that the documentary's lack of disclosure that the narrator's male guardian occupied a post in the Hamas-controlled government was substantially inaccurate.
"Consequently that the viewers did not have essential details which may have been extremely pertinent to their judgment of the narrator and the information he shared.
"Confidence is at the heart of the connection between a media organization and its viewers, notably for a state-funded media outlet such as the British Broadcasting Corporation.
"This error had the possibility to damage the significantly high degrees of trust that audiences would have placed in a documentary produced by the BBC about the Israel-Gaza war."
The programme was pulled from the BBC's streaming service in February after the narrator's familial connections emerged, and in this past July an internal BBC review concluded it violated the organization's journalistic standards on accuracy.
A representative for the broadcaster commented: "The authority's determination is in line with the findings of Peter Johnston's review, that there was a major oversight in the programme in relation to the corporation's content standards on factual correctness, which corresponds to regulation 2.2 of the authority's broadcasting regulations.
"We issued an apology for this and we accept the authority's determination in full. We will adhere to the penalty as soon as the date and wording are finalised."
