The public service broadcaster was found to have committed a "serious breach" of industry standards by omitting to mention that the presenter of a film about Gaza was the child of a Hamas official, according to British broadcasting authority Ofcom.
An inquiry by the broadcasting watchdog into the programme Gaza: How to Survive a Warzone has determined that the documentary was "materially misleading".
The BBC's director general had already issued an apology, noting there had been "a major oversight in relation to truthfulness".
The authority has ordered the BBC to air a prime-time declaration about its findings.
"Given this constitutes a significant violation of our code, we are directing the BBC to broadcast a announcement of our conclusions against it on BBC Two at 21:00, with a date to be determined," it said.
'Potential to Undermine Confidence'
The regulator's announcement stated: "The inquiry we conducted concluded that the documentary's omission to reveal that the voice's male guardian served in a position in the Hamas-controlled authority was substantially inaccurate.
"Consequently that the audience did not have essential details which may have been extremely pertinent to their evaluation of the voice and the information he provided.
"Confidence is at the center of the relationship between a broadcaster and its viewers, notably for a national broadcasting corporation such as the BBC.
"This oversight had the potential to undermine the very considerable degrees of credibility that the public would have placed in a factual film from the broadcaster about the Israel-Gaza war."
The documentary was removed from iPlayer in February after the narrator's family links were revealed, and in the month of July an corporation's own inquiry found it violated the organization's editorial guidelines on factual correctness.
A representative for the broadcaster commented: "The regulator's decision is in line with the findings of the internal assessment, that there was a major oversight in the film in relation to the broadcaster's journalistic policies on accuracy, which reflects regulation 2.2 of the authority's broadcasting regulations.
"We have apologised for this and we comply with the authority's determination in full. We will follow the sanction as soon as the timing and wording are determined."
