The British broadcaster committed a "serious breach" of broadcasting rules by not revealing that the narrator of a film about the Gaza situation was the son of a Hamas official, as determined by UK media regulator Ofcom.
An inquiry by Ofcom into Gaza: How to Survive a Warzone has concluded that the documentary was "materially misleading".
The BBC's director general had earlier expressed regret, stating there had been "a serious error in relation to accuracy".
The regulator has instructed the broadcaster to transmit a prime-time announcement about its conclusions.
"Given this constitutes a major infringement of our code, we are instructing the corporation to air a announcement of our conclusions against it on BBC Two at 21:00, with a schedule to be finalised," it said.
'Potential to Undermine Credibility'
The regulator's report stated: "Our probe found that the film's failure to disclose that the presenter's male guardian occupied a position in the Hamas-run authority was substantially inaccurate.
"This implied that the public did not have critical information which may have been highly relevant to their assessment of the voice and the details he presented.
"Confidence is at the center of the relationship between a media organization and its viewers, particularly for a national broadcasting corporation such as the public broadcaster.
"This oversight had the risk to undermine the exceptionally strong levels of credibility that the public would have invested in a factual film from the broadcaster about the conflict in Gaza."
The programme was removed from the online platform in the month of February after the narrator's familial connections came to light, and in July an corporation's own inquiry determined it infringed the organization's editorial guidelines on truthfulness.
A corporation official said: "The authority's determination is in line with the results 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 corresponds to Rule 2.2 of the regulator's media standards.
"We issued an apology for this and we accept the authority's determination in its entirety. We will comply with the directive as soon as the schedule and wording are finalised."
