The British broadcaster was found to have committed a "serious breach" of industry standards by not revealing that the voice of a documentary about the Gaza situation was the son of a Hamas administrator, as ruled by regulatory body Ofcom.
An investigation by the broadcasting watchdog into the programme Gaza: How to Survive a Warzone has determined that the film was "substantially inaccurate".
The head of the BBC had already issued an apology, saying there had been "a significant failing in relation to accuracy".
The regulator has instructed the corporation to broadcast a evening declaration about its conclusions.
"Given this constitutes a serious breach of our code, we are instructing the broadcaster to transmit a announcement of our determinations against it on BBC Two at 9pm, with a date to be confirmed," it said.
'Potential to Erode Confidence'
The authority's statement said: "Our investigation concluded that the documentary's lack of disclosure that the voice's father served in a post in the Hamas-controlled government was significantly deceptive.
"Consequently that the public did not have vital facts which may have been extremely pertinent to their assessment of the presenter and the information he shared.
"Credibility is at the center of the connection between a broadcaster and its public, notably for a national broadcasting corporation such as the British Broadcasting Corporation.
"This error had the potential to undermine the significantly high levels of credibility that viewers would have placed in a documentary produced by the BBC about the conflict in Gaza."
The programme was withdrawn from the BBC's streaming service in last February after the presenter's family links emerged, and in this past July an internal BBC review determined it violated the corporation's editorial guidelines on factual correctness.
A representative for the broadcaster said: "The Ofcom ruling is in accordance with the conclusions of Peter Johnston's review, that there was a major oversight in the programme in relation to the corporation's content standards on factual correctness, which aligns with regulation 2.2 of Ofcom's Broadcasting Code.
"We have apologised for this and we accept Ofcom's decision in complete. We will comply with the sanction as soon as the schedule and wording are confirmed."
