The public service broadcaster engaged in a "serious breach" of industry standards by failing to disclose that the voice of a programme about the Gaza situation was the child of a Hamas representative, as ruled by British broadcasting authority Ofcom.
An probe by the media regulator into Gaza: How to Survive a Warzone has found that the documentary was "substantially inaccurate".
The head of the BBC had earlier expressed regret, saying there had been "a serious error in relation to accuracy".
The authority has instructed the corporation to transmit a evening declaration about its conclusions.
"As this represents a major infringement of our code, we are ordering the broadcaster to transmit a statement of our conclusions against it on BBC2 at 21:00, with a date to be determined," it said.
'Risk to Undermine Trust'
The watchdog's announcement said: "Our investigation determined that the documentary's omission to reveal that the narrator's parent served in a position in the Hamas-administered government was materially misleading.
"It meant that the public did not have vital facts which may have been highly relevant to their evaluation of the voice and the information he provided.
"Confidence is at the heart of the relationship between a media organization and its viewers, especially for a national broadcasting corporation such as the public broadcaster.
"This error had the possibility to undermine the very considerable degrees of confidence that the public would have invested in a documentary produced by the BBC about the Israel-Gaza war."
The film was withdrawn from the online platform in last February after the presenter's family links emerged, and in the month of July an broadcaster's internal assessment determined it violated the organization's editorial guidelines on truthfulness.
A representative for the broadcaster said: "The Ofcom ruling is in accordance with the findings of the corporation's inquiry, that there was a major oversight in the documentary in relation to the BBC's Editorial Guidelines on truthfulness, which corresponds to clause 2.2 of the regulator's media standards.
"We expressed regret for this and we agree with the regulator's ruling in its entirety. We will adhere to the sanction as soon as the schedule and wording are determined."
