The BBC was found to have committed a "serious breach" of media regulations by not revealing that the narrator of a documentary about the Gaza conflict was the child of a Hamas administrator, 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 programme was "substantially inaccurate".
The head of the BBC had already issued an apology, saying there had been "a serious error in relation to accuracy".
The regulator has ordered the broadcaster to transmit a evening announcement about its conclusions.
"Since this amounts to a major infringement of our regulations, we are instructing the broadcaster to broadcast a statement of our conclusions against it on the BBC's second channel at 9pm, with a schedule to be confirmed," it said.
'Potential to Undermine Trust'
The watchdog's statement said: "The inquiry we conducted determined that the documentary's failure to disclose that the voice's father served in a post in the Hamas-administered administration was significantly deceptive.
"This implied that the audience did not have vital facts which may have been extremely pertinent to their judgment of the presenter and the details he provided.
"Credibility is at the core of the bond between a media organization and its public, particularly for a public service broadcaster such as the British Broadcasting Corporation.
"This oversight had the possibility to erode the very considerable amounts of credibility that audiences would have invested in a documentary produced by the BBC about the conflict in Gaza."
The documentary was withdrawn from the online platform in the month of February after the presenter's personal associations emerged, and in this past July an broadcaster's internal assessment determined it violated the corporation's journalistic standards on factual correctness.
A corporation official said: "The authority's determination is in agreement with the conclusions of Peter Johnston's review, that there was a serious error in the film in relation to the BBC's Editorial Guidelines on truthfulness, which aligns with Rule 2.2 of Ofcom's Broadcasting Code.
"We issued an apology for this and we agree with Ofcom's decision in full. We will follow the directive as soon as the schedule and wording are finalised."
