The British broadcaster committed a "major breach" of broadcasting rules by not revealing that the presenter of a film about Gaza was the son of a Hamas administrator, according to British broadcasting authority Ofcom.
An probe by the broadcasting watchdog into Gaza: How to Survive a Warzone has concluded that the documentary was "materially misleading".
The chief executive of the broadcaster had previously apologised, stating there had been "a major oversight in relation to factual correctness".
The authority has directed the BBC to air a evening statement about its findings.
"Given this constitutes a serious breach of our regulations, we are instructing the BBC to air a message of our determinations against it on BBC2 at nine o'clock in the evening, with a timing to be finalised," it said.
'Potential to Damage Trust'
The authority's announcement stated: "Our investigation concluded that the documentary's omission to reveal that the narrator's parent served in a role in the Hamas-run administration was materially misleading.
"It meant that the public did not have essential details which may have been very significant to their assessment of the voice and the details he provided.
"Trust is at the core of the bond between a broadcaster and its viewers, notably for a public service broadcaster such as the British Broadcasting Corporation.
"This failing had the possibility to erode the very considerable levels of credibility that viewers would have put in a factual film from the broadcaster about the conflict in Gaza."
The film was withdrawn from the BBC's streaming service in February after the boy's family links came to light, and in the month of July an corporation's own inquiry concluded it breached the broadcaster's journalistic standards on accuracy.
A BBC spokesperson commented: "The Ofcom ruling is in line with the results of the corporation's inquiry, that there was a serious error in the film in relation to the BBC's Editorial Guidelines on factual correctness, which aligns with regulation 2.2 of the regulator's media standards.
"We have apologised for this and we agree with the authority's determination in full. We will follow the sanction as soon as the timing and language are confirmed."