The public service broadcaster committed a "serious breach" of media regulations by not revealing that the presenter of a programme about the Gaza situation was the offspring of a Hamas representative, as determined by UK media regulator Ofcom.
An inquiry by the media regulator into Gaza: How to Survive a Warzone has concluded that the programme was "significantly deceptive".
The BBC's director general had earlier expressed regret, stating there had been "a major oversight in relation to factual correctness".
The regulator has instructed the corporation to air a prime-time announcement about its decisions.
"As this represents a major infringement of our rules, we are instructing the broadcaster to broadcast a statement of our determinations against it on the BBC's second channel at 9pm, with a schedule to be finalised," it said.
'Possibility to Damage Confidence'
The regulator's statement said: "Our probe determined that the film's failure to disclose that the voice's parent held a post in the Hamas-administered administration was significantly deceptive.
"Consequently that the viewers did not have vital facts which may have been very significant to their evaluation of the narrator and the content he provided.
"Trust is at the heart of the connection between a media organization and its viewers, notably for a national broadcasting corporation such as the BBC.
"This oversight had the potential to damage the significantly high degrees of trust that audiences would have put in a factual film from the broadcaster about the Gaza conflict."
The documentary was withdrawn from iPlayer in the month of February after the narrator's personal associations were revealed, and in this past July an broadcaster's internal assessment concluded it infringed the broadcaster's editorial guidelines on accuracy.
A BBC spokesperson stated: "The authority's determination is in line with the findings of the internal assessment, that there was a significant failing in the documentary in relation to the corporation's content standards on truthfulness, which reflects clause 2.2 of Ofcom's Broadcasting Code.
"We expressed regret for this and we accept the regulator's ruling in complete. We will comply with the penalty as soon as the date and wording are determined."
