The BBC committed a "major breach" of industry standards by failing to disclose that the narrator of a documentary about Gaza was the child of a Hamas official, as ruled by UK media regulator Ofcom.
An inquiry by the broadcasting watchdog into Gaza: How to Survive a Warzone has concluded that the documentary was "significantly deceptive".
The chief executive of the broadcaster had previously apologised, noting there had been "a significant failing in relation to factual correctness".
Ofcom has directed the BBC to transmit a prime-time statement about its conclusions.
"As this represents a serious breach of our regulations, we are directing the BBC to transmit a statement of our conclusions against it on BBC Two at 9pm, with a timing to be determined," the statement read.
'Possibility to Damage Confidence'
The watchdog's announcement stated: "The inquiry we conducted concluded that the film's failure to disclose that the narrator's parent served in a role in the Hamas-controlled government was significantly deceptive.
"This implied that the viewers did not have critical information which may have been very significant to their judgment of the narrator and the information he provided.
"Confidence is at the core of the connection between a media organization and its public, particularly for a state-funded media outlet such as the British Broadcasting Corporation.
"This error had the possibility to erode the very considerable amounts of confidence that viewers would have invested in a BBC factual programme about the Israel-Gaza war."
The programme was removed from the BBC's streaming service in February after the boy's personal associations were revealed, and in July an broadcaster's internal assessment found it infringed the corporation's journalistic standards on accuracy.
A representative for the broadcaster said: "The Ofcom ruling is in agreement with the results of Peter Johnston's review, that there was a significant failing in the film in relation to the BBC's Editorial Guidelines on accuracy, which reflects regulation 2.2 of the regulator's media standards.
"We have apologised for this and we agree with the regulator's ruling in complete. We will comply with the sanction as soon as the schedule and wording are confirmed."
