The public service broadcaster was found to have committed a "serious breach" of broadcasting rules by failing to disclose that the narrator of a film about the Gaza situation was the son of a Hamas representative, as ruled by UK media regulator Ofcom.
An probe by Ofcom into Gaza: How to Survive a Warzone has concluded that the documentary was "significantly deceptive".
The BBC's director general had already issued an apology, stating there had been "a serious error in relation to truthfulness".
Ofcom has directed the BBC to broadcast a prime-time declaration about its decisions.
"As this represents a major infringement of our regulations, we are instructing the BBC to transmit a message of our findings against it on the BBC's second channel at 9pm, with a date to be determined," it said.
'Potential to Undermine Confidence'
The regulator's statement said: "The inquiry we conducted determined that the programme's failure to disclose that the presenter's parent occupied a position in the Hamas-run administration was materially misleading.
"This implied that the audience did not have vital facts which may have been extremely pertinent to their judgment of the narrator and the information he presented.
"Confidence is at the center of the relationship between a broadcaster and its public, notably for a national broadcasting corporation such as the British Broadcasting Corporation.
"This error had the risk to erode the significantly high degrees of trust that viewers would have put in a factual film from the broadcaster about the Israel-Gaza war."
The documentary was removed from iPlayer in last February after the narrator's personal associations emerged, and in this past July an corporation's own inquiry determined it infringed the corporation's editorial guidelines on truthfulness.
A BBC spokesperson stated: "The regulator's decision is in accordance with the findings of Peter Johnston's review, that there was a significant failing in the programme in relation to the corporation's content standards on truthfulness, which corresponds to clause 2.2 of Ofcom's Broadcasting Code.
"We expressed regret for this and we accept Ofcom's decision in complete. We will comply with the sanction as soon as the date and wording are finalised."
