The British broadcaster was found to have committed a "significant breach" of broadcasting rules by not revealing that the narrator of a programme about the Gaza situation was the son of a Hamas official, according to regulatory body Ofcom.
An inquiry by the media regulator into Gaza: How to Survive a Warzone has determined that the programme was "significantly deceptive".
The head of the BBC had previously apologised, stating there had been "a serious error in relation to truthfulness".
Ofcom has ordered the corporation to broadcast a evening statement about its findings.
"Since this amounts to a serious breach of our regulations, we are ordering the broadcaster to broadcast a message of our findings against it on the BBC's second channel at 21:00, with a date to be finalised," it said.
'Risk to Erode Credibility'
The watchdog's statement stated: "Our investigation concluded that the programme's omission to reveal that the presenter's male guardian served in a post in the Hamas-controlled government was significantly deceptive.
"It meant that the public did not have critical information which may have been very significant to their evaluation of the voice and the details he shared.
"Trust is at the center of the bond between a television network and its public, especially for a public service broadcaster such as the BBC.
"This oversight had the potential to undermine the significantly high levels of credibility that audiences would have placed in a factual film from the broadcaster about the Israel-Gaza war."
The film was withdrawn from the BBC's streaming service in last February after the boy's familial connections were revealed, and in July an corporation's own inquiry found it violated the corporation's editorial guidelines on factual correctness.
A representative for the broadcaster commented: "The authority's determination is in accordance with the conclusions of Peter Johnston's review, that there was a serious error in the programme in relation to the corporation's content standards on truthfulness, which corresponds to clause 2.2 of Ofcom's Broadcasting Code.
"We have apologised for this and we comply with the regulator's ruling in its entirety. We will comply with the sanction as soon as the schedule and wording are determined."
