The public service broadcaster was found to have committed a "major breach" of industry standards by failing to disclose that the narrator of a documentary about the Gaza conflict was the child of a Hamas administrator, as determined by regulatory body Ofcom.
An probe by the media regulator into Gaza: How to Survive a Warzone has concluded that the programme was "substantially inaccurate".
The BBC's director general had already issued an apology, saying there had been "a significant failing in relation to truthfulness".
The authority has directed the broadcaster to broadcast a peak-time declaration about its findings.
"Given this constitutes a serious breach of our regulations, we are ordering the BBC to air a message of our conclusions against it on BBC2 at 9pm, with a date to be finalised," it said.
'Potential to Damage Trust'
The regulator's statement declared: "Our probe concluded that the programme's lack of disclosure that the voice's parent served in a post in the Hamas-run administration was materially misleading.
"Consequently that the public did not have critical information which may have been very significant to their assessment of the narrator and the information he shared.
"Credibility is at the center of the bond between a broadcaster and its audience, particularly for a national broadcasting corporation such as the BBC.
"This failing had the possibility to undermine the exceptionally strong levels of trust that viewers would have put in a BBC factual programme about the conflict in Gaza."
The documentary was withdrawn from the online platform in February after the boy's family links were revealed, and in the month of July an corporation's own inquiry determined it infringed the organization's content policies on factual correctness.
A representative for the broadcaster said: "The regulator's decision is in line with the findings of the internal assessment, that there was a serious error in the programme in relation to the corporation's content standards on factual correctness, which aligns with Rule 2.2 of Ofcom's Broadcasting Code.
"We have apologised for this and we accept the authority's determination in complete. We will comply with the sanction as soon as the timing and language are confirmed."
