The British broadcaster was found to have committed a "major breach" of media regulations by failing to disclose that the narrator of a film about the Gaza situation was the son of a Hamas administrator, as ruled by UK media regulator Ofcom.
An investigation by the broadcasting watchdog into the programme Gaza: How to Survive a Warzone has found that the film was "substantially inaccurate".
The head of the BBC had already issued an apology, noting there had been "a serious error in relation to accuracy".
The regulator has ordered the broadcaster to transmit a evening declaration about its conclusions.
"Since this amounts to a significant violation of our rules, we are directing the corporation to broadcast a announcement of our conclusions against it on BBC2 at nine o'clock in the evening, with a schedule to be determined," the regulator stated.
'Potential to Damage Confidence'
The watchdog's announcement said: "The inquiry we conducted determined that the programme's omission to reveal that the voice's parent served in a role in the Hamas-administered administration was materially misleading.
"This implied that the viewers did not have essential details which may have been very significant to their assessment of the narrator and the information he presented.
"Confidence is at the heart of the connection between a broadcaster and its viewers, notably for a public service broadcaster such as the public broadcaster.
"This oversight had the risk to erode the exceptionally strong amounts of credibility that the public would have put in a factual film from the broadcaster about the Israel-Gaza war."
The documentary was withdrawn from the online platform in February after the narrator's family links were revealed, and in the month of July an broadcaster's internal assessment determined it breached the broadcaster's content policies on accuracy.
A corporation official said: "The regulator's decision is in line with the results of Peter Johnston's review, that there was a serious error in the documentary in relation to the BBC's Editorial Guidelines on accuracy, which aligns with regulation 2.2 of the regulator's media standards.
"We expressed regret for this and we accept the regulator's ruling in full. We will comply with the penalty as soon as the schedule and wording are finalised."
