The public service broadcaster committed a "significant breach" of media regulations by not revealing that the narrator of a programme about Gaza was the son of a Hamas official, as ruled by regulatory body Ofcom.
An investigation by the broadcasting watchdog into Gaza: How to Survive a Warzone has determined that the film was "significantly deceptive".
The chief executive of the broadcaster had already issued an apology, noting there had been "a major oversight in relation to truthfulness".
The regulator has ordered the BBC to transmit a prime-time announcement about its findings.
"As this represents a serious breach of our regulations, we are ordering the corporation to air a statement of our conclusions against it on the BBC's second channel at 21:00, with a date to be finalised," the statement read.
'Risk to Damage Credibility'
The regulator's announcement stated: "Our probe concluded that the programme's failure to disclose that the voice's male guardian occupied a position in the Hamas-controlled government was significantly deceptive.
"Consequently that the public did not have vital facts which may have been highly relevant to their assessment of the presenter and the information he provided.
"Credibility is at the core of the connection between a media organization and its audience, especially for a public service broadcaster such as the British Broadcasting Corporation.
"This oversight had the potential to undermine the very considerable levels of trust that the public would have placed in a documentary produced by the BBC about the Gaza conflict."
The programme was pulled from the BBC's streaming service in the month of February after the presenter's family links came to light, and in July an broadcaster's internal assessment determined it breached the organization's journalistic standards on accuracy.
A corporation official said: "The Ofcom ruling is in line with the findings of Peter Johnston's review, that there was a significant failing in the film in relation to the BBC's Editorial Guidelines on truthfulness, which aligns with Rule 2.2 of the authority's broadcasting regulations.
"We have apologised for this and we accept the regulator's ruling in complete. We will comply with the sanction as soon as the schedule and wording are finalised."
