The public service broadcaster committed a "major breach" of broadcasting rules by omitting to mention that the voice of a programme about the Gaza conflict was the child of a Hamas administrator, as determined by regulatory body Ofcom.
An investigation by the broadcasting watchdog into the programme Gaza: How to Survive a Warzone has determined that the programme was "materially misleading".
The BBC's director general had earlier expressed regret, stating there had been "a significant failing in relation to accuracy".
The regulator has directed the corporation to broadcast a prime-time declaration about its decisions.
"As this represents a serious breach of our regulations, we are instructing the BBC to broadcast a statement of our conclusions against it on BBC Two at nine o'clock in the evening, with a date to be determined," the statement read.
'Possibility to Damage Credibility'
The authority's statement said: "Our investigation determined that the programme's omission to reveal that the narrator's father occupied a role in the Hamas-controlled authority was significantly deceptive.
"This implied that the audience did not have vital facts which may have been very significant to their judgment of the narrator and the content he presented.
"Credibility is at the heart of the connection between a television network and its public, especially for a national broadcasting corporation such as the British Broadcasting Corporation.
"This failing had the risk to erode the exceptionally strong degrees of credibility that the public would have placed in a BBC factual programme about the Israel-Gaza war."
The documentary was withdrawn from the BBC's streaming service in last February after the boy's personal associations were revealed, and in this past July an corporation's own inquiry found it breached the corporation's editorial guidelines on truthfulness.
A BBC spokesperson commented: "The authority's determination is in agreement with the findings of the internal assessment, that there was a significant failing in the documentary in relation to the broadcaster's journalistic policies on truthfulness, which aligns with clause 2.2 of the regulator's media standards.
"We issued an apology for this and we comply with the authority's determination in full. We will comply with the penalty as soon as the timing and wording are confirmed."
