The BBC committed a "significant breach" of broadcasting rules by failing to disclose that the presenter of a programme about the Gaza situation was the son of a Hamas representative, as determined by regulatory body Ofcom.
An inquiry by the media regulator into the documentary titled Gaza: How to Survive a Warzone has determined that the programme was "significantly deceptive".
The head of the BBC had already issued an apology, noting there had been "a major oversight in relation to factual correctness".
Ofcom has instructed the broadcaster to transmit a prime-time declaration about its conclusions.
"As this represents a major infringement of our regulations, we are directing the BBC to transmit a message of our determinations against it on BBC Two at 21:00, with a timing to be confirmed," the statement read.
'Potential to Damage Credibility'
The authority's statement said: "The inquiry we conducted found that the documentary's lack of disclosure that the voice's parent held a post in the Hamas-controlled administration was significantly deceptive.
"This implied that the audience did not have essential details which may have been highly relevant to their judgment of the voice and the content he provided.
"Credibility is at the core of the bond between a broadcaster and its public, particularly for a national broadcasting corporation such as the British Broadcasting Corporation.
"This oversight had the risk to erode the exceptionally strong degrees of trust that viewers would have invested in a factual film from the broadcaster about the Gaza conflict."
The documentary was removed from the BBC's streaming service in the month of February after the narrator's personal associations emerged, and in the month of July an corporation's own inquiry determined it infringed the corporation's content policies on truthfulness.
A BBC spokesperson said: "The regulator's decision is in agreement with the results of the internal assessment, that there was a major oversight in the film in relation to the corporation's content standards on factual correctness, which aligns with regulation 2.2 of the authority's broadcasting regulations.
"We issued an apology for this and we accept the authority's determination in its entirety. We will comply with the sanction as soon as the timing and wording are determined."
