The BBC committed a "major breach" of media regulations by failing to disclose that the voice of a film about the Gaza situation was the son of a Hamas official, as ruled by British broadcasting authority Ofcom.
An probe by Ofcom into Gaza: How to Survive a Warzone has concluded that the programme was "materially misleading".
The head of the BBC had previously apologised, saying there had been "a major oversight in relation to factual correctness".
The authority has directed the corporation to transmit a evening statement about its conclusions.
"As this represents a serious breach of our regulations, we are directing the corporation to transmit a statement of our conclusions against it on the BBC's second channel at 9pm, with a date to be finalised," the regulator stated.
'Potential to Erode Credibility'
The watchdog's announcement said: "The inquiry we conducted determined that the documentary's omission to reveal that the voice's parent served in a position in the Hamas-administered government was significantly deceptive.
"It meant that the viewers did not have essential details which may have been highly relevant to their judgment of the voice and the content he provided.
"Trust is at the center of the bond between a broadcaster and its viewers, especially for a public service broadcaster such as the BBC.
"This oversight had the possibility to damage the exceptionally strong degrees of trust that viewers would have placed in a BBC factual programme about the Gaza conflict."
The documentary was removed from the BBC's streaming service in February after the narrator's family links came to light, and in the month of July an broadcaster's internal assessment concluded it breached the corporation's content policies on accuracy.
A corporation official commented: "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 broadcaster's journalistic policies on accuracy, which reflects regulation 2.2 of Ofcom's Broadcasting Code.
"We expressed regret for this and we agree with Ofcom's decision in its entirety. We will adhere to the directive as soon as the date and wording are finalised."
