The British broadcaster was found to have committed a "significant breach" of media regulations by failing to disclose that the presenter of a film about the Gaza situation was the son of a Hamas official, according to British broadcasting authority Ofcom.
An probe by the media regulator into Gaza: How to Survive a Warzone has found that the film was "substantially inaccurate".
The head of the BBC had earlier expressed regret, noting there had been "a significant failing in relation to accuracy".
Ofcom has ordered the broadcaster to air a prime-time declaration about its findings.
"Since this amounts to a serious breach of our rules, we are instructing the corporation to transmit a message of our determinations against it on BBC2 at 21:00, with a schedule to be determined," it said.
'Possibility to Erode Trust'
The watchdog's announcement declared: "Our investigation found that the programme's lack of disclosure that the narrator's parent held a post in the Hamas-administered authority was substantially inaccurate.
"Consequently that the public did not have vital facts which may have been very significant to their judgment of the narrator and the details he presented.
"Trust is at the core of the relationship between a broadcaster and its viewers, particularly for a national broadcasting corporation such as the public broadcaster.
"This failing had the possibility to damage the very considerable levels of trust that the public would have placed in a BBC factual programme about the Gaza conflict."
The film was withdrawn from the online platform in the month of February after the narrator's familial connections emerged, and in this past July an corporation's own inquiry concluded it breached the corporation's editorial guidelines on factual correctness.
A corporation official stated: "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 accuracy, which aligns with clause 2.2 of Ofcom's Broadcasting Code.
"We expressed regret for this and we comply with the authority's determination in complete. We will adhere to the penalty as soon as the schedule and wording are finalised."
