The British broadcaster committed a "serious breach" of media regulations by omitting to mention that the voice of a programme about the Gaza conflict was the son of a Hamas official, as determined by British broadcasting authority Ofcom.
An inquiry by the media regulator into Gaza: How to Survive a Warzone has concluded that the film was "materially misleading".
The BBC's director general had earlier expressed regret, noting there had been "a significant failing in relation to accuracy".
Ofcom has instructed the corporation to air a prime-time statement about its decisions.
"Given this constitutes a major infringement of our code, we are directing the broadcaster to air a message of our findings against it on BBC Two at 21:00, with a schedule to be determined," the statement read.
'Risk to Undermine Trust'
The watchdog's statement said: "Our probe determined that the programme's omission to reveal that the voice's male guardian occupied a position in the Hamas-controlled authority was materially misleading.
"It meant that the public did not have essential details which may have been highly relevant to their judgment of the voice and the details he presented.
"Credibility is at the center of the bond between a television network and its audience, particularly for a public service broadcaster such as the British Broadcasting Corporation.
"This error had the potential to erode the exceptionally strong levels of confidence that viewers would have put in a BBC factual programme about the conflict in Gaza."
The documentary was pulled from iPlayer in last February after the boy's family links were revealed, and in July an internal BBC review concluded it breached the organization's editorial guidelines on factual correctness.
A representative for the broadcaster commented: "The regulator's decision is in accordance with the results of Peter Johnston's review, that there was a significant failing 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 expressed regret for this and we comply with Ofcom's decision in complete. We will adhere to the directive as soon as the timing and language are confirmed."