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 the Gaza conflict was the son of a Hamas representative, as ruled by British broadcasting authority Ofcom.
An inquiry by the media regulator into the documentary titled Gaza: How to Survive a Warzone has concluded that the film was "substantially inaccurate".
The BBC's director general had earlier expressed regret, saying there had been "a major oversight in relation to truthfulness".
The regulator has ordered the BBC to transmit a evening declaration about its conclusions.
"Given this constitutes a significant violation of our regulations, we are ordering the BBC to broadcast a message of our conclusions against it on BBC2 at 9pm, with a schedule to be finalised," the regulator stated.
'Risk to Erode Confidence'
The authority's announcement stated: "Our investigation determined that the documentary's lack of disclosure that the narrator's male guardian held a post in the Hamas-administered administration was materially misleading.
"It meant that the audience did not have critical information which may have been very significant to their judgment of the narrator and the details he shared.
"Confidence is at the center of the connection between a television network and its viewers, notably for a public service broadcaster such as the public broadcaster.
"This oversight had the potential to undermine the significantly high degrees of confidence that audiences would have put in a factual film from the broadcaster about the conflict in Gaza."
The documentary was withdrawn from the BBC's streaming service in February after the presenter's familial connections were revealed, and in this past July an corporation's own inquiry determined it violated the organization's content policies on truthfulness.
A representative for the broadcaster stated: "The regulator's decision is in agreement with the findings of Peter Johnston's review, that there was a significant failing in the programme in relation to the broadcaster's journalistic policies on factual correctness, which reflects Rule 2.2 of the authority's broadcasting regulations.
"We have apologised for this and we accept the regulator's ruling in its entirety. We will comply with the sanction as soon as the schedule and language are confirmed."
