The British broadcaster was found to have committed a "significant breach" of broadcasting rules by omitting to mention that the voice of a film about Gaza was the child of a Hamas official, according to UK media regulator Ofcom.
An investigation by Ofcom into the programme Gaza: How to Survive a Warzone has found that the programme was "substantially inaccurate".
The BBC's director general had earlier expressed regret, noting there had been "a serious error in relation to truthfulness".
The authority has instructed the broadcaster to broadcast a peak-time announcement about its conclusions.
"Since this amounts to a serious breach of our code, we are directing the BBC to transmit a statement of our determinations against it on the BBC's second channel at nine o'clock in the evening, with a date to be finalised," the statement read.
'Possibility to Undermine Credibility'
The authority's statement said: "Our investigation found that the documentary's failure to disclose that the narrator's parent held a post in the Hamas-run authority was substantially inaccurate.
"Consequently that the viewers did not have critical information which may have been highly relevant to their evaluation of the voice and the details he presented.
"Confidence is at the heart of the bond between a media organization and its viewers, especially for a national broadcasting corporation such as the BBC.
"This oversight had the risk to erode the significantly high degrees of credibility that viewers would have placed in a factual film from the broadcaster about the Gaza conflict."
The film was removed from the BBC's streaming service in the month of February after the boy's familial connections were revealed, and in July an broadcaster's internal assessment determined it infringed the corporation's content policies on accuracy.
A representative for the broadcaster stated: "The authority's determination is in line with the conclusions of Peter Johnston's review, that there was a serious error in the film in relation to the BBC's Editorial Guidelines on factual correctness, which corresponds to Rule 2.2 of the regulator's media standards.
"We have apologised for this and we accept the authority's determination in full. We will adhere to the sanction as soon as the date and wording are determined."
