The BBC engaged in a "significant breach" of broadcasting rules by omitting to mention that the voice of a film about the Gaza conflict was the offspring of a Hamas administrator, as ruled by UK media regulator Ofcom.
An probe by the broadcasting watchdog into the programme Gaza: How to Survive a Warzone has concluded that the film was "substantially inaccurate".
The BBC's director general had previously apologised, noting there had been "a major oversight in relation to factual correctness".
The authority has ordered the broadcaster to air a evening declaration about its conclusions.
"Since this amounts to a major infringement of our rules, we are ordering the broadcaster to transmit a message of our determinations against it on the BBC's second channel at nine o'clock in the evening, with a date to be confirmed," the regulator stated.
'Potential to Erode Credibility'
The authority's report said: "Our probe determined that the programme's lack of disclosure that the narrator's parent held a role in the Hamas-run administration was substantially inaccurate.
"It meant that the viewers did not have essential details which may have been very significant to their judgment of the narrator and the details he shared.
"Credibility is at the center of the bond between a broadcaster and its public, notably for a national broadcasting corporation such as the public broadcaster.
"This failing had the possibility to damage the exceptionally strong amounts of trust that audiences would have placed in a factual film from the broadcaster about the conflict in Gaza."
The film was withdrawn from the BBC's streaming service in the month of February after the narrator's personal associations came to light, and in July an internal BBC review determined it violated the organization's editorial guidelines on accuracy.
A corporation official commented: "The authority's determination is in line with the results of the corporation's inquiry, that there was a serious error in the documentary in relation to the corporation's content standards on accuracy, which aligns with Rule 2.2 of the regulator's media standards.
"We have apologised for this and we accept the regulator's ruling in complete. We will comply with the directive as soon as the date and wording are finalised."
