The BBC committed a "serious breach" of media regulations by failing to disclose that the narrator of a documentary about Gaza was the child of a Hamas administrator, as determined by British broadcasting authority Ofcom.
An probe by Ofcom into the programme Gaza: How to Survive a Warzone has concluded that the documentary was "substantially inaccurate".
The BBC's director general had earlier expressed regret, saying there had been "a serious error in relation to truthfulness".
The authority has instructed the BBC to broadcast a evening announcement about its conclusions.
"Given this constitutes a significant violation of our rules, we are instructing the corporation to broadcast a statement of our findings against it on BBC2 at 9pm, with a timing to be confirmed," the statement read.
'Possibility to Undermine Confidence'
The watchdog's statement stated: "The inquiry we conducted determined that the programme's failure to disclose that the voice's father served in a role in the Hamas-controlled government was significantly deceptive.
"Consequently that the audience did not have critical information which may have been very significant to their judgment of the voice and the content he provided.
"Trust is at the center of the connection between a media organization and its audience, notably for a public service broadcaster such as the public broadcaster.
"This error had the possibility to undermine the exceptionally strong degrees of trust that the public would have placed in a documentary produced by the BBC about the Israel-Gaza war."
The documentary was removed from the online platform in last February after the presenter's family links emerged, and in the month of July an broadcaster's internal assessment concluded it breached the corporation's journalistic standards on accuracy.
A corporation official commented: "The regulator's decision is in line with the conclusions of the internal assessment, that there was a serious error in the film in relation to the BBC's Editorial Guidelines on accuracy, which reflects regulation 2.2 of the regulator's media standards.
"We have apologised for this and we agree with the regulator's ruling in full. We will follow the penalty as soon as the schedule and wording are finalised."
