The BBC committed a "serious breach" of broadcasting rules by not revealing that the voice of a documentary about Gaza was the child of a Hamas representative, as ruled by British broadcasting authority Ofcom.
An inquiry by the broadcasting watchdog into the programme Gaza: How to Survive a Warzone has found that the film was "significantly deceptive".
The head of the BBC had earlier expressed regret, saying there had been "a major oversight in relation to truthfulness".
The authority has instructed the broadcaster to transmit a evening announcement about its findings.
"Given this constitutes a serious breach of our code, we are instructing the corporation to broadcast a announcement of our determinations against it on the BBC's second channel at nine o'clock in the evening, with a schedule to be determined," the statement read.
'Potential to Erode Confidence'
The authority's statement declared: "The inquiry we conducted found that the film's omission to reveal that the narrator's father held a position in the Hamas-run authority was significantly deceptive.
"Consequently that the public did not have vital facts which may have been extremely pertinent to their evaluation of the narrator and the content he shared.
"Credibility is at the heart of the bond between a television network and its viewers, notably for a public service broadcaster such as the British Broadcasting Corporation.
"This oversight had the potential to undermine the very considerable levels of trust that viewers would have put in a factual film from the broadcaster about the Israel-Gaza war."
The documentary was removed from iPlayer in last February after the narrator's personal associations came to light, and in the month of July an internal BBC review determined it violated the broadcaster's journalistic standards on truthfulness.
A corporation official commented: "The regulator's decision is in accordance with the conclusions of Peter Johnston's review, that there was a major oversight in the film in relation to the BBC's Editorial Guidelines on factual correctness, which reflects regulation 2.2 of Ofcom's Broadcasting Code.
"We have apologised for this and we comply with Ofcom's decision in complete. We will adhere to the penalty as soon as the timing and language are determined."
