The BBC engaged in a "major breach" of media regulations by omitting to mention that the voice of a documentary about Gaza was the son of a Hamas official, as determined by regulatory body Ofcom.
An investigation by the media regulator into Gaza: How to Survive a Warzone has concluded that the programme was "significantly deceptive".
The BBC's director general had earlier expressed regret, noting there had been "a major oversight in relation to factual correctness".
Ofcom has instructed the BBC to transmit a evening statement about its findings.
"Since this amounts to a major infringement of our rules, we are directing the BBC to air a statement of our determinations against it on BBC Two at 21:00, with a schedule to be finalised," the regulator stated.
'Potential to Damage Trust'
The authority's report declared: "Our probe determined that the programme's lack of disclosure that the voice's parent held a post in the Hamas-administered government was substantially inaccurate.
"It meant that the public did not have essential details which may have been highly relevant to their assessment of the voice and the details he provided.
"Trust is at the center of the connection between a broadcaster and its public, particularly for a national broadcasting corporation such as the public broadcaster.
"This oversight had the possibility to erode the significantly high degrees of credibility that viewers would have invested in a BBC factual programme about the Israel-Gaza war."
The programme was removed from the online platform in February after the narrator's family links emerged, and in this past July an corporation's own inquiry concluded it breached the broadcaster's journalistic standards on truthfulness.
A representative for the broadcaster stated: "The Ofcom ruling is in accordance with the results 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 authority's broadcasting regulations.
"We issued an apology for this and we accept the authority's determination in full. We will adhere to the penalty as soon as the schedule and language are confirmed."
