The BBC committed a "significant breach" of broadcasting rules by omitting to mention that the presenter of a film about the Gaza conflict was the child of a Hamas representative, as ruled by regulatory body Ofcom.
An probe by the media regulator into Gaza: How to Survive a Warzone has concluded that the programme was "materially misleading".
The head of the BBC had already issued an apology, noting there had been "a significant failing in relation to accuracy".
The authority has ordered the broadcaster to transmit a prime-time statement about its conclusions.
"Given this constitutes a serious breach of our code, we are directing the broadcaster to transmit a statement of our conclusions against it on BBC2 at nine o'clock in the evening, with a schedule to be determined," the statement read.
'Potential to Damage Trust'
The authority's report declared: "Our probe concluded that the film's lack of disclosure that the voice's male guardian held a position in the Hamas-controlled government was substantially inaccurate.
"It meant that the viewers did not have vital facts which may have been highly relevant to their assessment of the presenter and the information he presented.
"Trust is at the core of the relationship between a broadcaster and its public, particularly for a public service broadcaster such as the public broadcaster.
"This error had the risk to damage the exceptionally strong amounts of confidence that the public would have put in a documentary produced by the BBC about the conflict in Gaza."
The documentary was withdrawn from the BBC's streaming service in last February after the narrator's family links came to light, and in the month of July an broadcaster's internal assessment determined it breached the corporation's journalistic standards on accuracy.
A BBC spokesperson commented: "The authority's determination is in agreement with the conclusions of the corporation's inquiry, that there was a major oversight in the documentary in relation to the corporation's content standards on accuracy, which corresponds to clause 2.2 of the regulator's media standards.
"We have apologised for this and we accept the authority's determination in its entirety. We will adhere to the sanction as soon as the timing and wording are determined."
