The BBC committed a "serious breach" of industry standards by failing to disclose that the voice of a programme about the Gaza situation was the child of a Hamas official, as determined by UK media regulator Ofcom.
An investigation by Ofcom into the documentary titled Gaza: How to Survive a Warzone has determined that the film was "materially misleading".
The BBC's director general had previously apologised, stating there had been "a significant failing in relation to factual correctness".
The authority has ordered the corporation to air a evening announcement about its conclusions.
"Since this amounts to a major infringement of our regulations, we are directing the corporation to broadcast a announcement of our conclusions against it on the BBC's second channel at 21:00, with a schedule to be confirmed," the regulator stated.
'Potential to Damage Confidence'
The authority's report said: "The inquiry we conducted concluded that the documentary's omission to reveal that the voice's father served in a post in the Hamas-controlled government was substantially inaccurate.
"Consequently that the viewers did not have vital facts which may have been very significant to their evaluation of the voice and the details he shared.
"Credibility is at the core of the connection between a broadcaster and its audience, especially for a national broadcasting corporation such as the public broadcaster.
"This oversight had the risk to erode the significantly high levels of confidence that viewers would have put in a BBC factual programme about the Israel-Gaza war."
The programme was removed from iPlayer in February after the presenter's familial connections came to light, and in this past July an corporation's own inquiry found it breached the corporation's editorial guidelines on truthfulness.
A BBC spokesperson said: "The authority's determination is in accordance with the results of the corporation's inquiry, that there was a significant failing in the film in relation to the BBC's Editorial Guidelines on truthfulness, which reflects clause 2.2 of Ofcom's Broadcasting Code.
"We expressed regret for this and we comply with the regulator's ruling in full. We will adhere to the penalty as soon as the schedule and wording are determined."
