The public service broadcaster committed a "serious breach" of media regulations by omitting to mention that the voice of a documentary about the Gaza situation was the son of a Hamas official, as determined by UK media regulator Ofcom.
An investigation by the media regulator into Gaza: How to Survive a Warzone has found that the programme was "materially misleading".
The BBC's director general had previously apologised, stating there had been "a major oversight in relation to factual correctness".
The authority has instructed the corporation to air a prime-time announcement about its findings.
"Since this amounts to a major infringement of our regulations, we are directing the broadcaster to broadcast a announcement of our conclusions against it on the BBC's second channel at nine o'clock in the evening, with a timing to be confirmed," it said.
'Possibility to Erode Credibility'
The watchdog's announcement declared: "Our investigation found that the film's lack of disclosure that the narrator's parent occupied a post in the Hamas-administered government was significantly deceptive.
"This implied that the viewers did not have critical information which may have been very significant to their assessment of the narrator and the information he provided.
"Credibility is at the core of the relationship between a media organization and its public, particularly for a public service broadcaster such as the BBC.
"This oversight had the potential to damage the very considerable degrees of credibility that audiences would have placed in a BBC factual programme about the Gaza conflict."
The programme was removed from the online platform in the month of February after the narrator's family links emerged, and in July an internal BBC review found it infringed the corporation's editorial guidelines on factual correctness.
A representative for the broadcaster stated: "The authority's determination is in accordance with the conclusions of the internal assessment, that there was a serious error in the documentary in relation to the BBC's Editorial Guidelines on truthfulness, which aligns with Rule 2.2 of Ofcom's Broadcasting Code.
"We have apologised for this and we agree with the regulator's ruling in full. We will adhere to the sanction as soon as the date and language are determined."
