The public service broadcaster committed a "serious breach" of media regulations by failing to disclose that the voice of a programme about Gaza was the son of a Hamas administrator, as ruled by British broadcasting authority Ofcom.
An inquiry by the broadcasting watchdog into Gaza: How to Survive a Warzone has determined that the film was "substantially inaccurate".
The BBC's director general had earlier expressed regret, noting there had been "a major oversight in relation to truthfulness".
The regulator has instructed the BBC to broadcast a peak-time declaration about its conclusions.
"As this represents a significant violation of our rules, we are instructing the corporation to air a message of our determinations against it on BBC2 at nine o'clock in the evening, with a timing to be finalised," the statement read.
'Potential to Erode Confidence'
The authority's announcement declared: "Our probe found that the film's omission to reveal that the voice's parent served in a post in the Hamas-administered authority was substantially inaccurate.
"It meant that the viewers did not have critical information which may have been extremely pertinent to their evaluation of the narrator and the details he presented.
"Confidence is at the center of the relationship between a broadcaster and its public, especially for a national broadcasting corporation such as the BBC.
"This failing had the possibility to damage the significantly high degrees of credibility that the public would have placed in a factual film from the broadcaster about the conflict in Gaza."
The film was pulled from the online platform in last February after the narrator's familial connections were revealed, and in this past July an internal BBC review concluded it violated the organization's content policies on truthfulness.
A representative for the broadcaster stated: "The authority's determination is in accordance with the results of the corporation's inquiry, that there was a serious error in the programme in relation to the corporation's content standards on truthfulness, which reflects clause 2.2 of the regulator's media standards.
"We have apologised for this and we agree with the regulator's ruling in full. We will comply with the penalty as soon as the schedule and language are determined."
