The BBC engaged in a "major breach" of industry standards by failing to disclose that the presenter of a film about the Gaza situation was the offspring of a Hamas administrator, as ruled by UK media regulator Ofcom.
An probe by the broadcasting watchdog into the programme Gaza: How to Survive a Warzone has determined that the documentary was "substantially inaccurate".
The chief executive of the broadcaster had earlier expressed regret, noting there had been "a significant failing in relation to factual correctness".
The authority has ordered the corporation to broadcast a peak-time statement about its findings.
"Given this constitutes a serious breach of our regulations, we are directing the BBC to air a message of our conclusions against it on BBC Two at nine o'clock in the evening, with a date to be confirmed," it said.
'Possibility to Erode Credibility'
The regulator's report said: "Our investigation determined that the documentary's lack of disclosure that the narrator's parent served in a position in the Hamas-run authority was significantly deceptive.
"It meant that the viewers did not have critical information which may have been highly relevant to their evaluation of the voice and the information he shared.
"Confidence is at the center of the bond between a media organization and its audience, notably for a public service broadcaster such as the BBC.
"This oversight had the potential to erode the significantly high levels of trust that viewers would have placed in a factual film from the broadcaster about the conflict in Gaza."
The programme was removed from the online platform in the month of February after the narrator's family links were revealed, and in the month of July an corporation's own inquiry determined it breached the corporation's editorial guidelines on accuracy.
A representative for the broadcaster said: "The regulator's decision is in line with the findings of the corporation's inquiry, that there was a major oversight in the programme in relation to the BBC's Editorial Guidelines on accuracy, which corresponds to regulation 2.2 of Ofcom's Broadcasting Code.
"We issued an apology for this and we accept Ofcom's decision in its entirety. We will follow the penalty as soon as the schedule and wording are confirmed."
