The British broadcaster was found to have committed a "significant breach" of industry standards by omitting to mention that the voice of a programme about Gaza was the offspring of a Hamas administrator, according to regulatory body Ofcom.
An inquiry by Ofcom into the programme Gaza: How to Survive a Warzone has concluded that the programme was "substantially inaccurate".
The BBC's director general had previously apologised, stating there had been "a serious error in relation to accuracy".
The regulator has directed the broadcaster to air a prime-time declaration about its conclusions.
"As this represents a serious breach of our regulations, we are directing the corporation to air a announcement of our determinations against it on BBC2 at 21:00, with a date to be finalised," the statement read.
'Risk to Erode Trust'
The authority's statement stated: "Our investigation concluded that the film's failure to disclose that the narrator's parent held a position in the Hamas-administered government was substantially inaccurate.
"Consequently that the audience did not have critical information which may have been very significant to their evaluation of the voice and the information he presented.
"Confidence is at the core of the bond between a television network and its public, especially for a public service broadcaster such as the BBC.
"This oversight had the risk to erode the very considerable degrees of credibility that viewers would have placed in a documentary produced by the BBC about the conflict in Gaza."
The programme was pulled from the online platform in last February after the narrator's personal associations were revealed, and in the month of July an internal BBC review determined it infringed the corporation's content policies on accuracy.
A BBC spokesperson commented: "The regulator's decision is in line with the results of the internal assessment, that there was a significant failing in the film in relation to the broadcaster's journalistic policies on truthfulness, which corresponds to Rule 2.2 of Ofcom's Broadcasting Code.
"We have apologised for this and we comply with the authority's determination in its entirety. We will adhere to the sanction as soon as the date and wording are confirmed."
