The public service broadcaster was found to have committed a "significant breach" of industry standards by failing to disclose that the voice of a film about the Gaza conflict was the child of a Hamas official, as ruled by British broadcasting authority Ofcom.
An inquiry by the broadcasting watchdog into Gaza: How to Survive a Warzone has concluded that the documentary was "substantially inaccurate".
The head of the BBC had previously apologised, saying there had been "a serious error in relation to truthfulness".
Ofcom has directed the broadcaster to transmit a peak-time announcement about its conclusions.
"Since this amounts to a major infringement of our code, we are instructing the broadcaster to transmit a message of our conclusions against it on BBC Two at 9pm, with a schedule to be finalised," the statement read.
'Risk to Damage Confidence'
The authority's statement declared: "The inquiry we conducted concluded that the film's omission to reveal that the narrator's parent held a role in the Hamas-administered government was significantly deceptive.
"Consequently that the audience did not have critical information which may have been extremely pertinent to their assessment of the presenter and the information he shared.
"Confidence is at the center of the bond between a television network and its viewers, especially for a state-funded media outlet such as the BBC.
"This error had the possibility to erode the significantly high degrees of trust that viewers would have invested in a documentary produced by the BBC about the Israel-Gaza war."
The film was pulled from the BBC's streaming service in last February after the narrator's personal associations emerged, and in the month of July an broadcaster's internal assessment found it infringed the corporation's journalistic standards on factual correctness.
A BBC spokesperson commented: "The regulator's decision is in agreement with the results of Peter Johnston's review, that there was a serious error in the film in relation to the broadcaster's journalistic policies on truthfulness, which corresponds to clause 2.2 of the regulator's media standards.
"We issued an apology for this and we comply with the regulator's ruling in full. We will adhere to the sanction as soon as the timing and wording are confirmed."
