The British broadcaster committed a "significant breach" of media regulations by failing to disclose that the presenter of a programme about the Gaza situation was the son of a Hamas official, as ruled by British broadcasting authority Ofcom.
An investigation 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 already issued an apology, noting there had been "a significant failing in relation to truthfulness".
Ofcom has ordered the corporation to air a prime-time declaration about its findings.
"Given this constitutes a major infringement of our code, we are ordering the BBC to air a announcement of our determinations against it on the BBC's second channel at nine o'clock in the evening, with a schedule to be confirmed," the statement read.
'Risk to Undermine Confidence'
The watchdog's report said: "Our probe determined that the documentary's lack of disclosure that the voice's father occupied a post in the Hamas-administered authority was substantially inaccurate.
"Consequently that the viewers did not have essential details which may have been extremely pertinent to their assessment of the narrator and the content he presented.
"Confidence is at the core of the connection between a media organization and its public, notably for a public service broadcaster such as the BBC.
"This oversight had the risk to undermine the significantly high degrees of trust that the public would have invested in a documentary produced by the BBC about the Israel-Gaza war."
The documentary was withdrawn from the online platform in last February after the presenter's family links came to light, and in July an internal BBC review concluded it violated the corporation's editorial guidelines on truthfulness.
A representative for the broadcaster said: "The authority's determination is in accordance with the results of the corporation's inquiry, that there was a significant failing in the programme in relation to the broadcaster's journalistic policies on factual correctness, which corresponds to regulation 2.2 of the regulator's media standards.
"We have apologised for this and we comply with Ofcom's decision in full. We will follow the penalty as soon as the date and wording are finalised."
