The British broadcaster was found to have committed a "major breach" of media regulations by not revealing that the presenter of a film about the Gaza conflict was the offspring of a Hamas official, as determined by regulatory body Ofcom.
An inquiry by the broadcasting watchdog into the programme Gaza: How to Survive a Warzone has concluded that the documentary was "significantly deceptive".
The BBC's director general had already issued an apology, saying there had been "a major oversight in relation to truthfulness".
Ofcom has directed the BBC to transmit a peak-time declaration about its findings.
"Given this constitutes a major infringement of our rules, we are instructing the corporation to air a statement of our findings against it on BBC2 at 21:00, with a date to be finalised," it said.
'Potential to Undermine Credibility'
The regulator's announcement said: "The inquiry we conducted concluded that the documentary's lack of disclosure that the presenter's parent served in a role in the Hamas-controlled authority was significantly deceptive.
"Consequently that the public did not have vital facts which may have been extremely pertinent to their evaluation of the voice and the details he provided.
"Trust is at the center of the bond between a media organization and its viewers, especially for a national broadcasting corporation such as the British Broadcasting Corporation.
"This failing had the potential to erode the exceptionally strong levels of credibility that the public would have invested in a BBC factual programme about the Israel-Gaza war."
The film was pulled from iPlayer in last February after the presenter's personal associations emerged, and in July an corporation's own inquiry found it violated the broadcaster's journalistic standards on accuracy.
A BBC spokesperson commented: "The Ofcom ruling is in line with the results of the internal assessment, that there was a serious error in the film in relation to the broadcaster's journalistic policies on truthfulness, which corresponds to regulation 2.2 of Ofcom's Broadcasting Code.
"We expressed regret for this and we accept Ofcom's decision in complete. We will adhere to the sanction as soon as the schedule and wording are confirmed."
