The British broadcaster was found to have committed a "significant breach" of media regulations by failing to disclose that the voice of a film about the Gaza conflict was the son of a Hamas representative, as ruled by UK media regulator Ofcom.
An inquiry by Ofcom into the documentary titled Gaza: How to Survive a Warzone has concluded that the film was "substantially inaccurate".
The chief executive of the broadcaster had already issued an apology, noting there had been "a major oversight in relation to truthfulness".
The authority has ordered the broadcaster to transmit a prime-time announcement about its findings.
"Since this amounts to a major infringement of our rules, we are instructing the corporation to broadcast a message of our findings against it on BBC2 at 21:00, with a schedule to be finalised," it said.
'Risk to Erode Credibility'
The watchdog's report said: "Our probe determined that the film's failure to disclose that the presenter's male guardian occupied a post in the Hamas-run authority was substantially inaccurate.
"Consequently that the viewers did not have essential details which may have been very significant to their assessment of the presenter and the details he presented.
"Trust is at the center of the relationship between a television network and its viewers, particularly for a national broadcasting corporation such as the British Broadcasting Corporation.
"This failing had the possibility to damage the significantly high degrees of credibility that viewers would have placed in a factual film from the broadcaster about the conflict in Gaza."
The documentary was withdrawn from iPlayer in last February after the narrator's family links came to light, and in this past July an internal BBC review found it breached the corporation's editorial guidelines on truthfulness.
A representative for the broadcaster stated: "The regulator's decision is in line with the results of the internal assessment, that there was a serious error in the film in relation to the broadcaster's journalistic policies on factual correctness, which reflects Rule 2.2 of the regulator's media standards.
"We have apologised for this and we accept the regulator's ruling in complete. We will adhere to the directive as soon as the date and language are finalised."
