The British broadcaster committed a "major breach" of industry standards by omitting to mention that the narrator of a programme about Gaza was the son of a Hamas official, as ruled by British broadcasting authority Ofcom.
An inquiry by the media regulator into the programme Gaza: How to Survive a Warzone has found that the documentary was "substantially inaccurate".
The BBC's director general had already issued an apology, saying there had been "a major oversight in relation to truthfulness".
Ofcom has directed the broadcaster to broadcast a prime-time announcement about its findings.
"Since this amounts to a significant violation of our regulations, we are ordering the broadcaster to broadcast a announcement of our determinations against it on BBC Two at nine o'clock in the evening, with a date to be finalised," it said.
'Possibility to Damage Confidence'
The watchdog's announcement stated: "Our investigation found that the programme's lack of disclosure that the voice's parent occupied a role in the Hamas-run government was materially misleading.
"It meant that the public did not have essential details which may have been very significant to their judgment of the narrator and the details he shared.
"Trust is at the core of the bond between a broadcaster and its audience, especially for a public service broadcaster such as the BBC.
"This error had the possibility to damage the very considerable degrees of trust that the public would have placed in a factual film from the broadcaster about the Gaza conflict."
The film was pulled from the BBC's streaming service in the month of February after the narrator's family links were revealed, and in this past July an internal BBC review determined it violated the corporation's journalistic standards on truthfulness.
A corporation official stated: "The regulator's decision is in agreement with the conclusions of the corporation's inquiry, that there was a serious error in the documentary in relation to the corporation's content standards on truthfulness, which reflects Rule 2.2 of the regulator's media standards.
"We issued an apology for this and we accept the regulator's ruling in complete. We will adhere to the penalty as soon as the schedule and wording are confirmed."
