The BBC was found to have committed a "significant breach" of media regulations by omitting to mention that the voice of a documentary about the Gaza conflict was the child of a Hamas official, as determined by regulatory body Ofcom.
An probe by Ofcom into Gaza: How to Survive a Warzone has concluded that the documentary was "substantially inaccurate".
The head of the BBC had earlier expressed regret, stating there had been "a serious error in relation to accuracy".
The authority has instructed the BBC to broadcast a peak-time statement about its conclusions.
"Given this constitutes a serious breach of our code, we are instructing the broadcaster to transmit a message of our conclusions against it on the BBC's second channel at nine o'clock in the evening, with a schedule to be finalised," the regulator stated.
'Possibility to Undermine Credibility'
The authority's statement stated: "Our probe found that the programme's omission to reveal that the narrator's male guardian served in a role in the Hamas-controlled government was materially misleading.
"This implied that the public did not have essential details which may have been highly relevant to their evaluation of the voice and the information he shared.
"Credibility is at the center of the bond between a media organization and its public, especially for a state-funded media outlet such as the British Broadcasting Corporation.
"This oversight had the risk to undermine the significantly high degrees of confidence that audiences would have put in a documentary produced by the BBC about the Israel-Gaza war."
The programme was pulled from the online platform in February after the presenter's personal associations came to light, and in July an broadcaster's internal assessment found it violated the corporation's content policies on truthfulness.
A BBC spokesperson stated: "The Ofcom ruling is in accordance with the findings of the corporation's inquiry, that there was a major oversight in the programme in relation to the BBC's Editorial Guidelines on accuracy, which corresponds to regulation 2.2 of Ofcom's Broadcasting Code.
"We issued an apology for this and we agree with Ofcom's decision in its entirety. We will comply with the penalty as soon as the date and wording are finalised."
