The BBC committed a "significant breach" of media regulations by not revealing that the voice of a documentary about the Gaza situation was the offspring of a Hamas official, as ruled by regulatory body Ofcom.
An investigation by the media regulator into the documentary titled Gaza: How to Survive a Warzone has concluded that the documentary was "substantially inaccurate".
The head of the BBC had earlier expressed regret, saying there had been "a significant failing in relation to accuracy".
The regulator has instructed the BBC to broadcast a peak-time statement about its decisions.
"Since this amounts to a serious breach of our code, we are directing the broadcaster to air a announcement of our determinations against it on BBC Two at 21:00, with a date to be confirmed," the regulator stated.
'Possibility to Undermine Trust'
The watchdog's report stated: "Our probe concluded that the documentary's lack of disclosure that the narrator's male guardian served in a position in the Hamas-run administration was significantly deceptive.
"Consequently that the public did not have essential details which may have been very significant to their judgment of the voice and the details he provided.
"Confidence is at the heart of the connection between a television network and its audience, especially for a state-funded media outlet such as the British Broadcasting Corporation.
"This failing had the potential to undermine the significantly high amounts of credibility that audiences would have placed in a documentary produced by the BBC about the conflict in Gaza."
The programme was withdrawn from iPlayer in last February after the presenter's familial connections came to light, and in this past July an corporation's own inquiry determined it infringed the broadcaster's journalistic standards on factual correctness.
A BBC spokesperson commented: "The authority's determination is in agreement with the conclusions of the internal assessment, that there was a significant failing in the programme in relation to the broadcaster's journalistic policies on truthfulness, which corresponds to regulation 2.2 of the authority's broadcasting regulations.
"We expressed regret for this and we agree with the authority's determination in complete. We will comply with the penalty as soon as the date and language are confirmed."
