The BBC was found to have committed a "serious breach" of media regulations by not revealing that the narrator of a documentary about Gaza was the offspring of a Hamas administrator, according to regulatory body Ofcom.
An probe by Ofcom into the programme Gaza: How to Survive a Warzone has found that the documentary was "significantly deceptive".
The BBC's director general had already issued an apology, saying there had been "a serious error in relation to factual correctness".
Ofcom has instructed the BBC to broadcast a prime-time declaration about its conclusions.
"Given this constitutes a serious breach of our regulations, we are directing the corporation to transmit a message of our determinations against it on BBC2 at 9pm, with a schedule to be finalised," the statement read.
'Potential to Erode Confidence'
The regulator's statement declared: "Our probe determined that the documentary's lack of disclosure that the presenter's father served in a role in the Hamas-administered authority was substantially inaccurate.
"This implied that the audience did not have critical information which may have been highly relevant to their judgment of the voice and the content he presented.
"Trust is at the core of the bond between a media organization and its viewers, notably for a public service broadcaster such as the public broadcaster.
"This oversight had the potential to erode the exceptionally strong amounts of credibility that audiences would have put in a documentary produced by the BBC about the conflict in Gaza."
The programme was withdrawn from the online platform in the month of February after the presenter's personal associations were revealed, and in this past July an broadcaster's internal assessment determined it infringed the corporation's journalistic standards on accuracy.
A corporation official commented: "The authority's determination is in accordance with the findings of the corporation's inquiry, that there was a serious error in the film in relation to the corporation's content standards 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 regulator's ruling in complete. We will adhere to the directive as soon as the schedule and wording are finalised."
