The British broadcaster engaged in a "major breach" of broadcasting rules by omitting to mention that the narrator of a programme about the Gaza conflict was the offspring of a Hamas official, as determined by UK media regulator Ofcom.
An inquiry by the media regulator into Gaza: How to Survive a Warzone has concluded that the programme was "substantially inaccurate".
The BBC's director general had earlier expressed regret, saying there had been "a significant failing in relation to accuracy".
Ofcom has instructed the BBC to transmit a evening declaration about its findings.
"Given this constitutes a major infringement of our code, we are instructing the broadcaster to air a announcement of our findings against it on the BBC's second channel at nine o'clock in the evening, with a date to be confirmed," it said.
'Possibility to Damage Credibility'
The regulator's report said: "Our investigation concluded that the film's lack of disclosure that the presenter's father occupied a role in the Hamas-run government was substantially inaccurate.
"It meant that the public did not have essential details which may have been highly relevant to their judgment of the narrator and the information he presented.
"Credibility is at the heart of the connection between a broadcaster and its audience, particularly for a public service broadcaster such as the public broadcaster.
"This failing had the possibility to undermine the exceptionally strong levels of credibility that viewers would have put in a factual film from the broadcaster about the Gaza conflict."
The film was removed from the BBC's streaming service in last February after the narrator's family links were revealed, and in this past July an internal BBC review found it violated the broadcaster's content policies on accuracy.
A corporation official said: "The Ofcom ruling is in accordance with the conclusions of the internal assessment, that there was a significant failing in the film in relation to the corporation's content standards on truthfulness, which corresponds to Rule 2.2 of the regulator's media standards.
"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 finalised."
