The BBC committed a "major breach" of media regulations by omitting to mention that the voice of a film about the Gaza situation was the offspring of a Hamas official, as determined by UK media regulator Ofcom.
An inquiry by the media regulator into the programme Gaza: How to Survive a Warzone has concluded that the documentary was "materially misleading".
The BBC's director general had previously apologised, saying there had been "a serious error in relation to factual correctness".
Ofcom has instructed the BBC to broadcast a peak-time statement about its findings.
"Since this amounts to a significant violation of our rules, we are ordering the broadcaster to air a message of our determinations against it on BBC2 at nine o'clock in the evening, with a schedule to be confirmed," the regulator stated.
'Potential to Damage Trust'
The regulator's statement said: "The inquiry we conducted concluded that the programme's omission to reveal that the presenter's parent served in a post in the Hamas-run administration was substantially inaccurate.
"Consequently that the public did not have vital facts which may have been very significant to their assessment of the narrator and the information he shared.
"Confidence is at the heart of the bond between a television network and its viewers, notably for a national broadcasting corporation such as the public broadcaster.
"This error had the potential to undermine the significantly high levels of trust that audiences would have invested in a documentary produced by the BBC about the Israel-Gaza war."
The programme was pulled from the BBC's streaming service in last February after the narrator's personal associations were revealed, and in this past July an broadcaster's internal assessment concluded it infringed the broadcaster's editorial guidelines on truthfulness.
A representative for the broadcaster commented: "The regulator's decision is in line with the findings of the corporation's inquiry, that there was a serious error in the film in relation to the BBC's Editorial Guidelines on accuracy, which corresponds to Rule 2.2 of the authority's broadcasting regulations.
"We have apologised for this and we accept Ofcom's decision in complete. We will follow the sanction as soon as the schedule and wording are determined."
