The BBC engaged in a "significant breach" of industry standards by omitting to mention that the presenter of a programme about the Gaza situation was the offspring of a Hamas administrator, as determined by regulatory body Ofcom.
An probe by the broadcasting watchdog into Gaza: How to Survive a Warzone has concluded that the film was "materially misleading".
The chief executive of the broadcaster had previously apologised, stating there had been "a serious error in relation to accuracy".
Ofcom has instructed the corporation to air a evening declaration about its decisions.
"As this represents a major infringement of our rules, we are ordering the BBC to transmit a announcement of our conclusions against it on the BBC's second channel at 21:00, with a timing to be finalised," the regulator stated.
'Potential to Undermine Confidence'
The regulator's report said: "Our probe found that the documentary's omission to reveal that the narrator's father served in a post in the Hamas-controlled authority was materially misleading.
"Consequently that the audience did not have critical information which may have been very significant to their assessment of the narrator and the information he presented.
"Credibility is at the center of the relationship between a broadcaster and its public, especially for a public service broadcaster such as the BBC.
"This error had the risk to damage the very considerable levels of trust that viewers would have placed in a documentary produced by the BBC about the Gaza conflict."
The documentary was withdrawn from the BBC's streaming service in the month of February after the narrator's familial connections were revealed, and in July an internal BBC review determined it infringed the corporation's editorial guidelines on accuracy.
A BBC spokesperson stated: "The authority's determination is in line with the conclusions of the internal assessment, that there was a significant failing in the programme in relation to the broadcaster's journalistic policies on truthfulness, which corresponds to regulation 2.2 of the authority's broadcasting regulations.
"We have apologised for this and we comply with the authority's determination in full. We will follow the directive as soon as the date and language are determined."
