The BBC engaged in a "significant breach" of media regulations by omitting to mention that the presenter of a film about the Gaza situation was the offspring of a Hamas official, as determined by regulatory body Ofcom.
An investigation by Ofcom into Gaza: How to Survive a Warzone has found that the film was "substantially inaccurate".
The chief executive of the broadcaster had previously apologised, stating there had been "a significant failing in relation to truthfulness".
The authority has ordered the BBC to broadcast a prime-time declaration about its decisions.
"As this represents a significant violation of our rules, we are instructing the corporation to broadcast a statement of our findings against it on BBC Two at 21:00, with a timing to be determined," the statement read.
'Risk to Undermine Confidence'
The regulator's report stated: "Our investigation found that the programme's omission to reveal that the voice's father held a position in the Hamas-administered government was significantly deceptive.
"This implied that the viewers did not have essential details which may have been very significant to their assessment of the voice and the details he shared.
"Credibility is at the core of the connection between a television network and its audience, particularly for a public service broadcaster such as the public broadcaster.
"This failing had the possibility to undermine the significantly high degrees of credibility that the public would have placed in a BBC factual programme about the Gaza conflict."
The documentary was pulled from the BBC's streaming service in last February after the narrator's personal associations emerged, and in July an internal BBC review determined it violated the organization's journalistic standards on factual correctness.
A BBC spokesperson stated: "The Ofcom ruling is in agreement with the results of the internal assessment, that there was a significant failing in the documentary in relation to the corporation's content standards on factual correctness, which corresponds to Rule 2.2 of Ofcom's Broadcasting Code.
"We issued an apology for this and we agree with the authority's determination in its entirety. We will adhere to the penalty as soon as the timing and language are finalised."
