The public service broadcaster was found to have committed a "significant breach" of industry standards by failing to disclose that the voice of a programme about Gaza was the offspring of a Hamas representative, according to regulatory body Ofcom.
An investigation by the broadcasting watchdog into the documentary titled Gaza: How to Survive a Warzone has found that the documentary was "significantly deceptive".
The chief executive of the broadcaster had previously apologised, stating there had been "a significant failing in relation to accuracy".
The regulator has ordered the broadcaster to transmit a prime-time announcement about its findings.
"As this represents a significant violation of our code, we are instructing the corporation to air a announcement of our findings against it on BBC2 at 9pm, with a schedule to be finalised," it said.
'Risk to Undermine Credibility'
The regulator's announcement stated: "The inquiry we conducted found that the documentary's lack of disclosure that the voice's father held a position in the Hamas-run authority was substantially inaccurate.
"Consequently that the audience did not have essential details which may have been extremely pertinent to their evaluation of the voice and the information he presented.
"Trust is at the center of the bond between a broadcaster and its audience, notably for a national broadcasting corporation such as the British Broadcasting Corporation.
"This oversight had the risk to erode the significantly high amounts of credibility that viewers would have invested in a BBC factual programme about the conflict in Gaza."
The programme was pulled from the BBC's streaming service in February after the narrator's family links were revealed, and in July an internal BBC review determined it infringed the organization's editorial guidelines on factual correctness.
A BBC spokesperson commented: "The Ofcom ruling is in line with the findings of Peter Johnston's review, that there was a serious error in the documentary in relation to the broadcaster's journalistic policies on accuracy, which corresponds to regulation 2.2 of the authority's broadcasting regulations.
"We have apologised for this and we comply with Ofcom's decision in full. We will adhere to the penalty as soon as the schedule and language are confirmed."
