The British broadcaster committed a "serious breach" of industry standards by failing to disclose that the presenter 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 concluded that the documentary was "materially misleading".
The head of the BBC had already issued an apology, stating there had been "a serious error in relation to factual correctness".
Ofcom has directed the BBC to transmit a peak-time declaration about its findings.
"Since this amounts to a significant violation of our code, we are directing the BBC to broadcast a message of our conclusions against it on the BBC's second channel at 9pm, with a date to be finalised," it said.
The regulator's report stated: "Our investigation determined that the film's omission to reveal that the presenter's father occupied a role in the Hamas-controlled government was significantly deceptive.
"Consequently that the audience did not have vital facts which may have been very significant to their assessment of the voice and the content he shared.
"Trust is at the center of the connection between a broadcaster and its audience, especially for a public service broadcaster such as the public broadcaster.
"This error had the possibility to damage the significantly high amounts of trust that audiences would have put in a documentary produced by the BBC about the Israel-Gaza war."
The film was removed from iPlayer in the month of February after the presenter's familial connections were revealed, and in July an broadcaster's internal assessment found it breached the corporation's editorial guidelines on truthfulness.
A BBC spokesperson said: "The authority's determination is in accordance with the results of the internal assessment, that there was a major oversight in the programme in relation to the broadcaster's journalistic policies on factual correctness, which reflects regulation 2.2 of the regulator's media standards.
"We have apologised for this and we agree with Ofcom's decision in its entirety. We will follow the penalty as soon as the date and language are determined."
Elena is a certified nutritionist with 10 years of experience in sports supplementation and wellness coaching.