The British broadcaster committed a "serious breach" of media regulations by omitting to mention that the narrator of a film about the Gaza situation was the offspring of a Hamas official, as determined by regulatory body Ofcom.
An investigation by the broadcasting watchdog into Gaza: How to Survive a Warzone has found that the programme was "substantially inaccurate".
The head of the BBC had earlier expressed regret, noting there had been "a significant failing in relation to truthfulness".
The authority has directed the broadcaster to broadcast a prime-time announcement about its conclusions.
"Given this constitutes a significant violation of our regulations, we are instructing the broadcaster to broadcast a announcement of our determinations against it on BBC2 at 9pm, with a date to be determined," the statement read.
'Risk to Damage Credibility'
The watchdog's statement said: "Our probe found that the film's omission to reveal that the narrator's male guardian served in a role in the Hamas-administered government was materially misleading.
"This implied that the public did not have vital facts which may have been extremely pertinent to their judgment of the voice and the details he shared.
"Confidence is at the heart of the relationship between a television network and its viewers, especially for a public service broadcaster such as the BBC.
"This oversight had the potential to damage the exceptionally strong degrees of confidence that audiences would have placed in a factual film from the broadcaster about the conflict in Gaza."
The documentary was pulled from the BBC's streaming service in February after the narrator's familial connections were revealed, and in this past July an internal BBC review determined it infringed the broadcaster's journalistic standards on factual correctness.
A corporation official commented: "The Ofcom ruling is in accordance with the results of the internal assessment, that there was a significant failing in the documentary in relation to the corporation's content standards on truthfulness, which reflects clause 2.2 of Ofcom's Broadcasting Code.
"We have apologised for this and we accept the authority's determination in complete. We will comply with the penalty as soon as the timing and language are determined."
