The British broadcaster was found to have committed a "serious breach" of industry standards by omitting to mention that the narrator of a programme about the Gaza situation was the offspring of a Hamas official, as ruled by UK media regulator Ofcom.
An investigation by the broadcasting watchdog into the programme Gaza: How to Survive a Warzone has determined that the programme was "substantially inaccurate".
The BBC's director general had earlier expressed regret, stating there had been "a major oversight in relation to truthfulness".
The authority has instructed the BBC to transmit a peak-time announcement about its findings.
"As this represents a significant violation of our code, we are directing the broadcaster to transmit a announcement of our determinations against it on BBC Two at nine o'clock in the evening, with a timing to be determined," it said.
'Potential to Damage Credibility'
The regulator's statement declared: "Our probe concluded that the documentary's failure to disclose that the presenter's male guardian occupied a role in the Hamas-controlled authority was substantially inaccurate.
"It meant that the public did not have essential details which may have been highly relevant to their evaluation of the voice and the information he presented.
"Trust is at the core of the bond between a television network and its audience, especially for a public service broadcaster such as the public broadcaster.
"This oversight had the potential to erode the very considerable degrees of confidence that the public would have invested in a BBC factual programme about the conflict in Gaza."
The programme was removed from the online platform in last February after the narrator's familial connections were revealed, and in July an corporation's own inquiry concluded it breached the broadcaster's content policies on truthfulness.
A representative for the broadcaster said: "The Ofcom ruling is in line with the findings of the corporation's inquiry, that there was a major oversight in the film in relation to the broadcaster's journalistic policies on factual correctness, which reflects clause 2.2 of Ofcom's Broadcasting Code.
"We expressed regret for this and we agree with the regulator's ruling in full. We will follow the penalty as soon as the date and wording are determined."
