The public service broadcaster was found to have committed a "significant breach" of broadcasting rules by omitting to mention that the voice of a documentary about the Gaza situation was the child of a Hamas official, as determined by regulatory body Ofcom.
An probe by the media regulator into Gaza: How to Survive a Warzone has found that the programme was "significantly deceptive".
The BBC's director general had earlier expressed regret, stating there had been "a major oversight in relation to accuracy".
The authority has ordered the broadcaster to broadcast a prime-time announcement about its conclusions.
"As this represents a significant violation of our code, we are ordering the BBC to transmit a message of our determinations against it on BBC2 at 21:00, with a date to be determined," the regulator stated.
'Possibility to Erode Trust'
The watchdog's statement declared: "Our investigation found that the programme's failure to disclose that the presenter's male guardian served in a position in the Hamas-controlled authority was substantially inaccurate.
"It meant that the audience did not have vital facts which may have been very significant to their judgment of the narrator and the information he provided.
"Trust is at the heart of the bond between a television network and its viewers, especially for a state-funded media outlet such as the BBC.
"This failing had the possibility to undermine the exceptionally strong levels of confidence that the public would have put in a BBC factual programme about the Gaza conflict."
The documentary was withdrawn from iPlayer in February after the presenter's familial connections came to light, and in July an corporation's own inquiry concluded it violated the corporation's editorial guidelines on factual correctness.
A representative for the broadcaster commented: "The authority's determination is in line with the conclusions of the corporation's inquiry, that there was a significant failing in the documentary in relation to the broadcaster's journalistic policies on factual correctness, which reflects regulation 2.2 of Ofcom's Broadcasting Code.
"We issued an apology for this and we accept the regulator's ruling in its entirety. We will follow the penalty as soon as the timing and language are finalised."
