The BBC engaged in a "major breach" of broadcasting rules by failing to disclose that the presenter of a programme about Gaza was the son of a Hamas official, as determined by UK media regulator Ofcom.
An probe by the broadcasting watchdog into Gaza: How to Survive a Warzone has determined that the programme was "materially misleading".
The head of the BBC had previously apologised, stating there had been "a significant failing in relation to accuracy".
The regulator has instructed the BBC to air a prime-time declaration about its conclusions.
"Since this amounts to a significant violation of our rules, we are instructing the corporation to transmit a statement of our conclusions against it on BBC2 at 21:00, with a date to be confirmed," it said.
'Risk to Damage Confidence'
The regulator's report declared: "Our probe concluded that the documentary's failure to disclose that the narrator's male guardian served in a role in the Hamas-controlled government was substantially inaccurate.
"Consequently that the public did not have essential details which may have been extremely pertinent to their assessment of the voice and the details he presented.
"Trust is at the center of the connection between a television network and its viewers, especially for a public service broadcaster such as the BBC.
"This failing had the possibility to undermine the exceptionally strong levels of confidence that viewers would have put in a BBC factual programme about the Israel-Gaza war."
The film was pulled from iPlayer in last February after the presenter's personal associations were revealed, and in this past July an corporation's own inquiry found it infringed the organization's content policies on truthfulness.
A BBC spokesperson said: "The authority's determination is in accordance with the results of Peter Johnston's review, that there was a serious error in the documentary in relation to the broadcaster's journalistic policies on factual correctness, which corresponds to clause 2.2 of the authority's broadcasting regulations.
"We issued an apology for this and we agree with the authority's determination in complete. We will adhere to the penalty as soon as the date and wording are determined."
