The BBC engaged in a "significant breach" of media regulations by omitting to mention that the narrator of a programme about the Gaza situation was the offspring of a Hamas administrator, according to regulatory body Ofcom.
An inquiry by the broadcasting watchdog into the programme Gaza: How to Survive a Warzone has found that the programme was "substantially inaccurate".
The head of the BBC had already issued an apology, saying there had been "a serious error in relation to factual correctness".
The regulator has directed the broadcaster to transmit a peak-time declaration about its conclusions.
"Since this amounts to a serious breach of our code, we are instructing the corporation to transmit a message of our determinations against it on BBC2 at 21:00, with a schedule to be confirmed," the regulator stated.
'Risk to Damage Trust'
The regulator's report declared: "Our probe determined that the film's failure to disclose that the presenter's parent served in a post in the Hamas-administered authority was significantly deceptive.
"This implied that the viewers did not have essential details which may have been highly relevant to their assessment of the voice and the information he provided.
"Credibility is at the center of the connection between a television network and its viewers, particularly for a public service broadcaster such as the British Broadcasting Corporation.
"This failing had the risk to damage the very considerable amounts of trust that viewers would have invested in a BBC factual programme about the Israel-Gaza war."
The documentary was removed from iPlayer in the month of February after the narrator's familial connections emerged, and in July an broadcaster's internal assessment found it violated the organization's journalistic standards on accuracy.
A BBC spokesperson said: "The authority's determination is in accordance with the conclusions of Peter Johnston's review, that there was a major oversight in the programme in relation to the BBC's Editorial Guidelines on accuracy, which corresponds to Rule 2.2 of the authority's broadcasting regulations.
"We issued an apology for this and we accept the authority's determination in its entirety. We will comply with the directive as soon as the schedule and language are finalised."
