The British broadcaster was found to have committed a "serious breach" of media regulations by omitting to mention that the voice of a programme about Gaza was the child of a Hamas administrator, as ruled by British broadcasting authority Ofcom.
An inquiry by Ofcom into the programme Gaza: How to Survive a Warzone has concluded that the film was "substantially inaccurate".
The BBC's director general had already issued an apology, saying there had been "a significant failing in relation to truthfulness".
The regulator has instructed the BBC to air a evening announcement about its findings.
"Since this amounts to a major infringement of our code, we are ordering the corporation to air a statement of our determinations against it on the BBC's second channel at nine o'clock in the evening, with a date to be finalised," the statement read.
'Potential to Undermine Confidence'
The watchdog's statement said: "Our investigation found that the film's omission to reveal that the voice's parent served in a role in the Hamas-administered administration was materially misleading.
"It meant that the public did not have essential details which may have been highly relevant to their assessment of the presenter and the details he presented.
"Confidence is at the center of the connection between a media organization and its audience, notably for a public service broadcaster such as the BBC.
"This failing had the potential to erode the significantly high amounts of trust that audiences would have put in a BBC factual programme about the conflict in Gaza."
The documentary was removed from the BBC's streaming service in the month of February after the presenter's personal associations emerged, and in this past July an internal BBC review found it breached the organization's journalistic standards on truthfulness.
A representative for the broadcaster stated: "The regulator's decision is in line with the results of the corporation's inquiry, that there was a serious error in the programme in relation to the BBC's Editorial Guidelines on factual correctness, which corresponds to Rule 2.2 of the regulator's media standards.
"We issued an apology for this and we comply with Ofcom's decision in complete. We will follow the penalty as soon as the timing and wording are determined."
