The British broadcaster engaged in a "significant breach" of industry standards by failing to disclose that the narrator of a documentary about the Gaza situation was the child of a Hamas representative, according to UK media regulator Ofcom.
An probe by Ofcom into Gaza: How to Survive a Warzone has found that the film was "significantly deceptive".
The BBC's director general had earlier expressed regret, saying there had been "a major oversight in relation to accuracy".
The authority has ordered the broadcaster to broadcast a evening announcement about its decisions.
"As this represents a major infringement of our regulations, we are instructing the BBC to air a announcement of our findings against it on the BBC's second channel at 9pm, with a schedule to be finalised," the statement read.
'Potential to Undermine Confidence'
The authority's report stated: "Our investigation determined that the programme's omission to reveal that the narrator's male guardian held a role in the Hamas-controlled authority was significantly deceptive.
"This implied that the viewers did not have critical information which may have been highly relevant to their assessment of the presenter and the details he shared.
"Trust is at the core of the connection between a broadcaster and its public, especially for a state-funded media outlet such as the British Broadcasting Corporation.
"This oversight had the possibility to damage the exceptionally strong amounts of trust that audiences would have put in a factual film from the broadcaster about the Gaza conflict."
The programme was removed from the BBC's streaming service in the month of February after the narrator's family links were revealed, and in the month of July an corporation's own inquiry found it infringed the organization's editorial guidelines on truthfulness.
A corporation official said: "The Ofcom ruling is in line with the conclusions of the internal assessment, that there was a significant failing in the documentary in relation to the BBC's Editorial Guidelines on accuracy, which corresponds to Rule 2.2 of Ofcom's Broadcasting Code.
"We issued an apology for this and we agree with the regulator's ruling in complete. We will follow the penalty as soon as the schedule and wording are confirmed."
