The British broadcaster was found to have committed a "significant breach" of media regulations by not revealing that the voice of a documentary about the Gaza conflict was the son of a Hamas official, as ruled by British broadcasting authority Ofcom.
An probe by the broadcasting watchdog into Gaza: How to Survive a Warzone has concluded that the programme was "significantly deceptive".
The BBC's director general had earlier expressed regret, noting there had been "a major oversight in relation to truthfulness".
The regulator has ordered the BBC to air a evening announcement about its decisions.
"Given this constitutes a significant violation of our rules, we are instructing the BBC to broadcast a message of our conclusions against it on BBC2 at 9pm, with a timing to be confirmed," the statement read.
'Risk to Erode Trust'
The authority's statement stated: "Our investigation concluded that the film's failure to disclose that the voice's parent served in a role in the Hamas-administered government was materially misleading.
"This implied that the audience did not have critical information which may have been very significant to their judgment of the presenter and the information he presented.
"Confidence is at the core of the bond between a broadcaster and its public, particularly for a public service broadcaster such as the public broadcaster.
"This error had the potential to erode the exceptionally strong levels of confidence that the public would have put in a factual film from the broadcaster about the conflict in Gaza."
The programme was withdrawn from the online platform in February after the boy's personal associations came to light, and in July an internal BBC review determined it infringed the corporation's journalistic standards on accuracy.
A representative for the broadcaster stated: "The authority's determination is in accordance with the conclusions of the internal assessment, that there was a serious error in the film in relation to the BBC's Editorial Guidelines on factual correctness, which reflects regulation 2.2 of the regulator's media standards.
"We have apologised for this and we accept the regulator's ruling in its entirety. We will follow the sanction as soon as the timing and wording are confirmed."
