The public service broadcaster committed a "major breach" of broadcasting rules by omitting to mention that the narrator of a film about Gaza was the offspring of a Hamas official, as determined by regulatory body Ofcom.
An inquiry by Ofcom into the programme Gaza: How to Survive a Warzone has concluded that the film was "substantially inaccurate".
The head of the BBC had previously apologised, stating there had been "a serious error in relation to truthfulness".
The authority has instructed the corporation to transmit a prime-time declaration about its findings.
"Given this constitutes a serious breach of our rules, we are instructing the broadcaster to broadcast a announcement of our findings against it on BBC2 at 21:00, with a date to be finalised," the regulator stated.
'Possibility to Undermine Credibility'
The watchdog's statement stated: "Our investigation found that the programme's failure to disclose that the voice's father served in a role in the Hamas-run administration was significantly deceptive.
"Consequently that the viewers did not have essential details which may have been very significant to their judgment of the voice and the details he presented.
"Confidence is at the heart of the connection between a media organization and its viewers, notably for a national broadcasting corporation such as the British Broadcasting Corporation.
"This failing had the potential to undermine the exceptionally strong levels of trust that viewers would have put in a factual film from the broadcaster about the conflict in Gaza."
The documentary was removed from the BBC's streaming service in February after the narrator's family links emerged, and in this past July an corporation's own inquiry concluded it violated the organization's content policies on factual correctness.
A corporation official commented: "The authority's determination is in agreement with the findings of the corporation's inquiry, that there was a significant failing in the film in relation to the BBC's Editorial Guidelines on factual correctness, which corresponds to regulation 2.2 of Ofcom's Broadcasting Code.
"We have apologised for this and we accept the authority's determination in complete. We will comply with the sanction as soon as the timing and language are determined."
