The public service broadcaster engaged in a "serious breach" of media regulations by not revealing that the voice of a documentary about Gaza was the offspring of a Hamas administrator, as ruled by regulatory body Ofcom.
An probe by the media regulator into Gaza: How to Survive a Warzone has concluded that the documentary was "substantially inaccurate".
The BBC's director general had already issued an apology, saying there had been "a significant failing in relation to factual correctness".
The regulator has instructed the broadcaster to transmit a evening announcement about its decisions.
"Since this amounts to a significant violation of our regulations, we are ordering the corporation to transmit a message of our conclusions against it on BBC Two at 9pm, with a schedule to be finalised," the regulator stated.
'Possibility to Undermine Trust'
The watchdog's announcement stated: "Our probe determined that the film's failure to disclose that the presenter's father held a post in the Hamas-controlled administration was significantly deceptive.
"It meant that the viewers did not have critical information which may have been extremely pertinent to their assessment of the presenter and the details he shared.
"Credibility is at the core of the connection between a broadcaster and its public, especially for a state-funded media outlet such as the public broadcaster.
"This error had the possibility to damage the exceptionally strong amounts of trust that audiences would have put in a factual film from the broadcaster about the Israel-Gaza war."
The programme was pulled from the online platform in the month of February after the boy's family links emerged, and in July an internal BBC review determined it violated the broadcaster's content policies on truthfulness.
A corporation official said: "The Ofcom ruling is in accordance with the findings of the corporation's inquiry, that there was a major oversight in the documentary in relation to the BBC's Editorial Guidelines on truthfulness, which aligns with clause 2.2 of the authority's broadcasting regulations.
"We have apologised for this and we comply with the regulator's ruling in its entirety. We will comply with the penalty as soon as the schedule and wording are determined."
