The British broadcaster was found to have committed a "major breach" of industry standards by omitting to mention that the narrator of a film about Gaza was the offspring of a Hamas administrator, as ruled by regulatory body Ofcom.
An probe by Ofcom into the programme Gaza: How to Survive a Warzone has found that the film was "significantly deceptive".
The head of the BBC had already issued an apology, saying there had been "a major oversight in relation to factual correctness".
Ofcom has directed the corporation to air a peak-time declaration about its findings.
"Given this constitutes a serious breach of our regulations, we are directing the BBC to broadcast a message of our findings against it on BBC2 at 9pm, with a timing to be finalised," the regulator stated.
'Possibility to Erode Trust'
The watchdog's statement said: "Our investigation concluded that the film's failure to disclose that the narrator's parent occupied a role in the Hamas-administered government was materially misleading.
"It meant that the audience did not have critical information which may have been highly relevant to their judgment of the voice and the details he shared.
"Credibility is at the heart of the bond between a television network and its public, particularly for a public service broadcaster such as the British Broadcasting Corporation.
"This oversight had the potential to erode the significantly high degrees of trust that audiences would have placed in a factual film from the broadcaster about the Gaza conflict."
The film was pulled from iPlayer in the month of February after the boy's personal associations were revealed, and in this past July an corporation's own inquiry found it violated the organization's editorial guidelines on truthfulness.
A representative for the broadcaster said: "The authority's determination is in agreement with the conclusions of Peter Johnston's review, that there was a serious error in the film in relation to the corporation's content standards on factual correctness, which reflects clause 2.2 of Ofcom's Broadcasting Code.
"We expressed regret for this and we agree with Ofcom's decision in full. We will comply with the penalty as soon as the schedule and wording are finalised."
