The public service broadcaster was found to have committed a "major breach" of industry standards by not revealing that the narrator of a film about the Gaza situation was the son of a Hamas representative, according to regulatory body Ofcom.
An probe by the broadcasting watchdog into the programme Gaza: How to Survive a Warzone has concluded that the programme was "substantially inaccurate".
The chief executive of the broadcaster had previously apologised, stating there had been "a serious error in relation to truthfulness".
The regulator has ordered the BBC to air a evening declaration about its findings.
"As this represents a major infringement of our code, we are directing the BBC to broadcast a message of our conclusions against it on the BBC's second channel at nine o'clock in the evening, with a date to be finalised," it said.
'Risk to Erode Trust'
The authority's statement said: "Our investigation determined that the documentary's lack of disclosure that the presenter's male guardian served in a position in the Hamas-controlled government was substantially inaccurate.
"This implied that the public did not have vital facts which may have been extremely pertinent to their assessment of the presenter and the details he provided.
"Credibility is at the core of the bond between a broadcaster and its viewers, particularly for a public service broadcaster such as the public broadcaster.
"This failing had the possibility to erode the exceptionally strong levels of credibility that viewers would have put in a documentary produced by the BBC about the Gaza conflict."
The film was withdrawn from the BBC's streaming service in last February after the boy's personal associations came to light, and in this past July an internal BBC review concluded it violated the broadcaster's editorial guidelines on factual correctness.
A representative for the broadcaster said: "The authority's determination is in agreement with the findings of the corporation's inquiry, that there was a significant failing in the programme in relation to the BBC's Editorial Guidelines on factual correctness, which reflects regulation 2.2 of the regulator's media standards.
"We expressed regret for this and we agree with Ofcom's decision in its entirety. We will follow the penalty as soon as the date and language are finalised."
