The British broadcaster engaged in a "serious breach" of media regulations by omitting to mention that the narrator of a programme about the Gaza situation was the offspring of a Hamas representative, as ruled by regulatory body Ofcom.
An probe by the broadcasting watchdog into Gaza: How to Survive a Warzone has found that the documentary was "significantly deceptive".
The head of the BBC had earlier expressed regret, noting there had been "a significant failing in relation to accuracy".
The regulator has instructed the broadcaster to air a evening declaration about its decisions.
"As this represents a significant violation of our rules, we are instructing the corporation to broadcast a statement of our determinations against it on the BBC's second channel at 21:00, with a timing to be confirmed," the statement read.
'Risk to Erode Confidence'
The authority's announcement stated: "Our probe found that the film's lack of disclosure that the voice's parent occupied a position in the Hamas-administered government was materially misleading.
"Consequently that the public did not have critical information which may have been very significant to their evaluation of the voice and the information he provided.
"Confidence is at the heart of the relationship between a broadcaster and its viewers, particularly for a public service broadcaster such as the British Broadcasting Corporation.
"This oversight had the potential to erode the significantly high levels of credibility that audiences would have put in a factual film from the broadcaster about the Gaza conflict."
The documentary was pulled from the BBC's streaming service in February after the presenter's family links came to light, and in the month of July an internal BBC review found it infringed the organization's editorial guidelines on factual correctness.
A representative for the broadcaster said: "The Ofcom ruling is in agreement with the findings of the internal assessment, that there was a major oversight in the documentary in relation to the BBC's Editorial Guidelines on factual correctness, which corresponds to Rule 2.2 of Ofcom's Broadcasting Code.
"We have apologised for this and we accept the authority's determination in its entirety. We will comply with the penalty as soon as the timing and language are confirmed."
