The British broadcaster committed a "serious breach" of industry standards by omitting to mention that the voice of a documentary about the Gaza conflict was the son of a Hamas official, according to British broadcasting authority Ofcom.
An investigation by Ofcom into Gaza: How to Survive a Warzone has concluded that the film was "substantially inaccurate".
The BBC's director general had earlier expressed regret, noting there had been "a major oversight in relation to truthfulness".
The authority has instructed the broadcaster to air a evening announcement about its findings.
"As this represents a major infringement of our regulations, we are instructing the broadcaster to broadcast a announcement of our conclusions against it on BBC2 at nine o'clock in the evening, with a date to be determined," it said.
'Possibility to Undermine Confidence'
The watchdog's statement stated: "The inquiry we conducted found that the film's lack of disclosure that the narrator's father held a role in the Hamas-administered authority was materially misleading.
"Consequently that the audience did not have vital facts which may have been highly relevant to their evaluation of the presenter and the information he presented.
"Trust is at the center of the bond between a television network and its audience, especially for a national broadcasting corporation such as the British Broadcasting Corporation.
"This failing had the possibility to erode the exceptionally strong degrees of credibility that audiences would have invested in a factual film from the broadcaster about the Gaza conflict."
The programme was pulled from the BBC's streaming service in last February after the boy's family links came to light, and in this past July an corporation's own inquiry determined it infringed the organization's content policies on factual correctness.
A corporation official stated: "The Ofcom ruling is in accordance with the conclusions of the internal assessment, that there was a serious error in the documentary in relation to the BBC's Editorial Guidelines on factual correctness, which corresponds to Rule 2.2 of the regulator's media standards.
"We expressed regret for this and we agree with the regulator's ruling in complete. We will follow the sanction as soon as the date and language are determined."
