The public service broadcaster was found to have committed a "major breach" of industry standards by not revealing that the narrator of a programme about the Gaza situation was the son of a Hamas official, according to UK media regulator Ofcom.
An investigation by Ofcom into the programme Gaza: How to Survive a Warzone has concluded that the film was "substantially inaccurate".
The BBC's director general had already issued an apology, noting there had been "a serious error in relation to truthfulness".
The regulator has instructed the corporation to broadcast a prime-time announcement about its findings.
"Given this constitutes a major infringement of our rules, we are ordering the corporation to air a announcement of our determinations against it on BBC Two at 21:00, with a date to be confirmed," it said.
'Potential to Damage Trust'
The regulator's report said: "Our investigation determined that the film's lack of disclosure that the narrator's male guardian occupied a post in the Hamas-administered authority was materially misleading.
"It meant that the public did not have essential details which may have been extremely pertinent to their judgment of the voice and the information he shared.
"Trust is at the heart of the connection between a television network and its public, especially for a state-funded media outlet such as the BBC.
"This failing had the possibility to erode the exceptionally strong levels of confidence that viewers would have placed in a documentary produced by the BBC about the Gaza conflict."
The documentary was pulled from the BBC's streaming service in last February after the boy's family links were revealed, and in the month of July an broadcaster's internal assessment determined it violated the organization's content policies on truthfulness.
A corporation official said: "The authority's determination is in agreement with the results of the corporation's inquiry, that there was a significant failing in the documentary in relation to the BBC's Editorial Guidelines on accuracy, which corresponds to regulation 2.2 of the regulator's media standards.
"We issued an apology for this and we comply with the regulator's ruling in full. We will adhere to the directive as soon as the timing and wording are confirmed."
