The public service broadcaster committed a "major breach" of industry standards by not revealing that the presenter of a film about Gaza was the son of a Hamas official, as ruled by British broadcasting authority Ofcom.
An probe by the media regulator into the documentary titled Gaza: How to Survive a Warzone has concluded that the film was "significantly deceptive".
The BBC's director general had already issued an apology, stating there had been "a major oversight in relation to truthfulness".
The regulator has instructed the BBC to broadcast a prime-time announcement about its conclusions.
"As this represents a significant violation of our code, we are directing the broadcaster to air a announcement of our conclusions against it on BBC Two at nine o'clock in the evening, with a timing to be finalised," it said.
'Potential to Damage Confidence'
The authority's statement declared: "The inquiry we conducted found that the documentary's failure to disclose that the narrator's male guardian held a post in the Hamas-controlled authority was significantly deceptive.
"It meant that the viewers did not have vital facts which may have been highly relevant to their judgment of the narrator and the content he provided.
"Trust is at the core of the bond between a television network and its public, especially for a public service broadcaster such as the BBC.
"This oversight had the potential to erode the very considerable levels of trust that viewers would have placed in a documentary produced by the BBC about the conflict in Gaza."
The film was withdrawn from iPlayer in last February after the boy's personal associations were revealed, and in this past July an broadcaster's internal assessment determined it infringed the corporation's content policies on factual correctness.
A representative for the broadcaster stated: "The Ofcom ruling is in line with the findings of the corporation's inquiry, that there was a serious error in the programme in relation to the BBC's Editorial Guidelines on accuracy, which corresponds to Rule 2.2 of the regulator's media standards.
"We have apologised for this and we agree with the regulator's ruling in its entirety. We will comply with the sanction as soon as the timing and wording are confirmed."
