The public service broadcaster engaged in a "serious breach" of industry standards by omitting to mention that the narrator of a film about the Gaza situation was the child of a Hamas official, as determined by UK media regulator Ofcom.
An investigation by the media regulator into Gaza: How to Survive a Warzone has concluded that the film was "significantly deceptive".
The chief executive of the broadcaster had already issued an apology, saying there had been "a serious error in relation to truthfulness".
The authority has directed the broadcaster to broadcast a prime-time announcement about its findings.
"Given this constitutes a major infringement of our rules, we are instructing the corporation to broadcast a statement of our conclusions against it on BBC Two at 9pm, with a schedule to be determined," the statement read.
'Potential to Damage Confidence'
The watchdog's statement stated: "The inquiry we conducted found that the documentary's omission to reveal that the presenter's parent held a role in the Hamas-run authority was significantly deceptive.
"This implied that the viewers did not have essential details which may have been very significant to their assessment of the presenter and the content he shared.
"Confidence is at the core of the relationship between a television network and its audience, especially for a national broadcasting corporation such as the public broadcaster.
"This oversight had the risk to erode the very considerable levels of trust that viewers would have put in a BBC factual programme about the Israel-Gaza war."
The documentary was withdrawn from the online platform in the month of February after the presenter's familial connections came to light, and in this past July an internal BBC review concluded it violated the broadcaster's editorial guidelines on truthfulness.
A corporation official said: "The Ofcom ruling is in agreement with the results of Peter Johnston's review, that there was a serious error in the film in relation to the broadcaster's journalistic policies on accuracy, which reflects regulation 2.2 of the authority's broadcasting regulations.
"We issued an apology for this and we comply with the authority's determination in its entirety. We will adhere to the directive as soon as the schedule and wording are finalised."
