The BBC engaged in a "serious breach" of media regulations by omitting to mention that the narrator of a programme about the Gaza conflict was the child of a Hamas administrator, as ruled by regulatory body Ofcom.
An investigation by Ofcom into the programme Gaza: How to Survive a Warzone has determined that the documentary was "substantially inaccurate".
The head of the BBC had previously apologised, stating there had been "a significant failing in relation to factual correctness".
The regulator has instructed the BBC to broadcast a peak-time statement about its findings.
"Since this amounts to a serious breach of our rules, we are directing the broadcaster to air a announcement of our determinations against it on BBC2 at 21:00, with a date to be finalised," it said.
'Possibility to Erode Credibility'
The watchdog's report said: "Our investigation concluded that the film's lack of disclosure that the voice's father held a role in the Hamas-run authority was materially misleading.
"This implied that the viewers did not have critical information which may have been very significant to their assessment of the narrator and the information he shared.
"Credibility is at the heart of the relationship between a media organization and its public, particularly for a state-funded media outlet such as the public broadcaster.
"This oversight had the potential to damage the exceptionally strong amounts of confidence that the public would have placed in a factual film from the broadcaster about the conflict in Gaza."
The documentary was removed from the online platform in the month of February after the presenter's family links emerged, and in July an broadcaster's internal assessment concluded it infringed the organization's content policies on factual correctness.
A corporation official commented: "The Ofcom ruling is in accordance with the conclusions of the internal assessment, that there was a major oversight in the film in relation to the BBC's Editorial Guidelines on accuracy, which corresponds to clause 2.2 of the regulator's media standards.
"We issued an apology for this and we comply with the authority's determination in complete. We will adhere to the sanction as soon as the date and language are determined."
