The BBC engaged in a "significant breach" of media regulations by omitting to mention that the presenter of a documentary about Gaza was the child of a Hamas representative, according to regulatory body Ofcom.
An investigation by Ofcom into the documentary titled Gaza: How to Survive a Warzone has found that the film was "substantially inaccurate".
The BBC's director general had earlier expressed regret, stating there had been "a serious error in relation to factual correctness".
Ofcom has ordered the corporation to transmit a peak-time announcement about its conclusions.
"As this represents a serious breach of our code, we are ordering the corporation to broadcast a announcement of our conclusions against it on the BBC's second channel at nine o'clock in the evening, with a date to be determined," it said.
'Potential to Erode Trust'
The regulator's announcement said: "Our investigation determined that the documentary's failure to disclose that the voice's father occupied a post in the Hamas-controlled government was substantially inaccurate.
"It meant that the audience did not have critical information which may have been very significant to their evaluation of the presenter and the information he presented.
"Trust is at the core of the relationship between a media organization and its public, especially for a state-funded media outlet such as the British Broadcasting Corporation.
"This error had the risk to erode the significantly high degrees of trust that the public would have invested in a factual film from the broadcaster about the Israel-Gaza war."
The documentary was pulled from iPlayer in the month of February after the boy's family links emerged, and in July an internal BBC review concluded it breached the organization's editorial guidelines on truthfulness.
A BBC spokesperson stated: "The Ofcom ruling is in agreement with the conclusions of Peter Johnston's review, that there was a major oversight in the programme in relation to the broadcaster's journalistic policies on truthfulness, which corresponds to clause 2.2 of the regulator's media standards.
"We expressed regret for this and we agree with the regulator's ruling in its entirety. We will follow the penalty as soon as the timing and wording are determined."
