The BBC engaged in a "significant breach" of industry standards by not revealing that the voice of a documentary about the Gaza situation was the offspring of a Hamas administrator, according to UK media regulator Ofcom.
An probe by the broadcasting watchdog into Gaza: How to Survive a Warzone has concluded that the film was "substantially inaccurate".
The chief executive of the broadcaster had previously apologised, stating there had been "a major oversight in relation to accuracy".
The authority has instructed the broadcaster to air a evening statement about its findings.
"Since this amounts to a major infringement of our regulations, we are directing the corporation to transmit a message of our findings against it on the BBC's second channel at 21:00, with a timing to be confirmed," the regulator stated.
'Possibility to Damage Trust'
The regulator's announcement declared: "The inquiry we conducted found that the programme's failure to disclose that the presenter's parent held a post in the Hamas-controlled government was substantially inaccurate.
"This implied 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.
"Credibility is at the heart of the connection between a broadcaster and its audience, notably for a public service broadcaster such as the public broadcaster.
"This failing had the potential to damage the exceptionally strong degrees of credibility that viewers would have put in a documentary produced by the BBC about the Israel-Gaza war."
The programme was removed from the BBC's streaming service in last February after the narrator's familial connections came to light, and in this past July an internal BBC review found it infringed the organization's content policies on accuracy.
A BBC spokesperson commented: "The Ofcom ruling is in accordance with the findings of the corporation's inquiry, that there was a major oversight in the programme in relation to the broadcaster's journalistic policies on accuracy, which reflects Rule 2.2 of the regulator's media standards.
"We issued an apology for this and we accept the authority's determination in its entirety. We will follow the sanction as soon as the timing and language are finalised."
