The BBC committed a "significant breach" of media regulations by omitting to mention that the voice of a film about Gaza was the son of a Hamas representative, as determined by UK media regulator Ofcom.
An inquiry by the broadcasting watchdog into Gaza: How to Survive a Warzone has concluded that the programme was "substantially inaccurate".
The BBC's director general had previously apologised, saying there had been "a significant failing in relation to accuracy".
Ofcom has instructed the BBC to broadcast a evening declaration about its findings.
"Given this constitutes a significant violation of our rules, we are instructing the broadcaster to air a statement of our determinations against it on BBC2 at nine o'clock in the evening, with a schedule to be finalised," it said.
'Possibility to Erode Credibility'
The regulator's report declared: "Our probe found that the documentary's failure to disclose that the narrator's father held a position in the Hamas-administered administration was significantly deceptive.
"It meant that the audience did not have critical information which may have been highly relevant to their evaluation of the voice and the content he shared.
"Credibility is at the center of the connection between a television network and its viewers, particularly for a state-funded media outlet such as the British Broadcasting Corporation.
"This failing had the possibility to erode the significantly high amounts of trust that the public would have put in a BBC factual programme about the Gaza conflict."
The documentary was pulled from the BBC's streaming service in the month of February after the presenter's personal associations emerged, and in the month of July an broadcaster's internal assessment found it breached the organization's editorial guidelines on accuracy.
A BBC spokesperson commented: "The authority's determination is in agreement with the conclusions of the corporation's inquiry, that there was a significant failing in the documentary in relation to the broadcaster's journalistic policies on accuracy, which reflects Rule 2.2 of the authority's broadcasting regulations.
"We issued an apology for this and we accept the regulator's ruling in full. We will adhere to the penalty as soon as the date and wording are finalised."
