The BBC was found to have committed a "significant breach" of media regulations by not revealing that the narrator of a programme about the Gaza situation was the child of a Hamas official, according to regulatory body Ofcom.
An investigation by the broadcasting watchdog into Gaza: How to Survive a Warzone has found that the programme was "substantially inaccurate".
The BBC's director general had already issued an apology, stating there had been "a significant failing in relation to accuracy".
Ofcom has instructed the broadcaster to broadcast a evening declaration about its findings.
"Since this amounts to a significant violation of our rules, we are directing the corporation to transmit a announcement of our conclusions against it on BBC2 at 21:00, with a date to be finalised," the statement read.
'Risk to Damage Trust'
The regulator's announcement said: "The inquiry we conducted determined that the documentary's lack of disclosure that the presenter's male guardian served in a position in the Hamas-controlled authority was substantially inaccurate.
"This implied that the public did not have vital facts which may have been very significant to their judgment of the presenter and the content he shared.
"Trust is at the center of the relationship between a media organization and its public, particularly for a public service broadcaster such as the public broadcaster.
"This failing had the risk to damage the very considerable amounts of trust that viewers would have put in a BBC factual programme about the Gaza conflict."
The documentary was withdrawn from the BBC's streaming service in February after the boy's personal associations were revealed, and in this past July an broadcaster's internal assessment determined it infringed the corporation's editorial guidelines on truthfulness.
A corporation official stated: "The authority's determination is in accordance with the results of Peter Johnston's review, that there was a significant failing in the programme in relation to the BBC's Editorial Guidelines on accuracy, which aligns with 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 directive as soon as the schedule and wording are confirmed."
