The British broadcaster committed a "significant breach" of media regulations by not revealing that the presenter of a documentary about the Gaza situation was the son of a Hamas official, as determined by regulatory body Ofcom.
An probe by Ofcom into the documentary titled Gaza: How to Survive a Warzone has found that the documentary was "significantly deceptive".
The chief executive of the broadcaster had earlier expressed regret, saying there had been "a serious error in relation to accuracy".
Ofcom has instructed the corporation to transmit a peak-time declaration about its conclusions.
"Since this amounts to a serious breach of our regulations, we are instructing the broadcaster to air a message of our conclusions against it on BBC2 at nine o'clock in the evening, with a date to be finalised," the statement read.
'Potential to Damage Trust'
The watchdog's statement declared: "Our investigation determined that the documentary's omission to reveal that the presenter's male guardian served in a role in the Hamas-administered administration was materially misleading.
"This implied that the audience did not have critical information which may have been highly relevant to their assessment of the voice and the information he shared.
"Trust is at the core of the connection between a media organization and its audience, particularly for a public service broadcaster such as the public broadcaster.
"This oversight had the risk to undermine the significantly high levels of credibility that viewers would have placed in a BBC factual programme about the conflict in Gaza."
The programme was pulled from iPlayer in the month of February after the narrator's family links emerged, and in July an internal BBC review determined it infringed the organization's journalistic standards on truthfulness.
A BBC spokesperson stated: "The authority's determination is in agreement with the findings of Peter Johnston's review, that there was a serious error in the programme in relation to the BBC's Editorial Guidelines on accuracy, which reflects clause 2.2 of the authority's broadcasting regulations.
"We expressed regret for this and we accept the regulator's ruling in its entirety. We will adhere to the penalty as soon as the date and language are determined."
