The public service broadcaster committed a "major breach" of broadcasting rules by not revealing that the presenter of a film about Gaza was the child of a Hamas representative, as ruled by UK media regulator Ofcom.
An investigation by the media regulator into the programme Gaza: How to Survive a Warzone has found that the film was "substantially inaccurate".
The chief executive of the broadcaster had already issued an apology, noting there had been "a serious error in relation to factual correctness".
The authority has instructed the broadcaster to transmit a peak-time declaration about its findings.
"Since this amounts to a significant violation of our regulations, we are directing the BBC to broadcast a announcement of our findings against it on BBC2 at 9pm, with a date to be confirmed," it said.
'Potential to Erode Confidence'
The authority's report stated: "The inquiry we conducted determined that the programme's lack of disclosure that the narrator's male guardian held a post in the Hamas-administered administration was materially misleading.
"This implied that the audience did not have essential details which may have been extremely pertinent to their judgment of the presenter and the content he shared.
"Credibility is at the core of the connection between a broadcaster and its audience, particularly for a national broadcasting corporation such as the British Broadcasting Corporation.
"This oversight had the possibility to undermine the significantly high degrees of trust that audiences would have placed in a documentary produced by the BBC about the conflict in Gaza."
The documentary was removed from the BBC's streaming service in last February after the narrator's family links came to light, and in this past July an corporation's own inquiry found it infringed the corporation's editorial guidelines on accuracy.
A representative for the broadcaster said: "The regulator's decision is in line with the findings of the internal assessment, that there was a significant failing in the documentary in relation to the broadcaster's journalistic policies on factual correctness, which corresponds to regulation 2.2 of the authority's broadcasting regulations.
"We have apologised for this and we comply with the authority's determination in full. We will adhere to the directive as soon as the date and language are confirmed."
