The British broadcaster engaged in a "significant breach" of media regulations by omitting to mention that the presenter of a documentary about the Gaza situation was the son of a Hamas representative, as determined by regulatory body Ofcom.
An investigation by Ofcom into the programme Gaza: How to Survive a Warzone has determined that the film was "materially misleading".
The BBC's director general had earlier expressed regret, stating there had been "a serious error in relation to truthfulness".
The authority has directed the corporation to air a peak-time announcement about its findings.
"As this represents a serious breach of our code, we are instructing the corporation to air a statement of our conclusions against it on BBC Two at nine o'clock in the evening, with a schedule to be finalised," the statement read.
'Potential to Damage Confidence'
The regulator's statement said: "The inquiry we conducted found that the film's failure to disclose that the narrator's male guardian occupied a post in the Hamas-controlled government was significantly deceptive.
"This implied that the viewers did not have vital facts which may have been very significant to their evaluation of the voice and the information he presented.
"Confidence is at the heart of the bond between a media organization and its viewers, especially for a state-funded media outlet such as the BBC.
"This error had the possibility to damage the very considerable amounts of trust that audiences would have placed in a factual film from the broadcaster about the conflict in Gaza."
The documentary was removed from iPlayer in last February after the narrator's family links were revealed, and in the month of July an corporation's own inquiry determined it breached the broadcaster's journalistic standards on truthfulness.
A representative for the broadcaster commented: "The authority's determination is in accordance with the findings of Peter Johnston's review, that there was a significant failing in the documentary in relation to the BBC's Editorial Guidelines on accuracy, which reflects Rule 2.2 of the regulator's media standards.
"We have apologised for this and we accept the regulator's ruling in full. We will adhere to the directive as soon as the date and wording are confirmed."
