The BBC was found to have committed a "significant breach" of industry standards by failing to disclose that the presenter of a documentary about Gaza was the son of a Hamas administrator, as ruled by UK media regulator Ofcom.
An investigation by the broadcasting watchdog into the programme Gaza: How to Survive a Warzone has determined that the programme was "materially misleading".
The chief executive of the broadcaster had earlier expressed regret, saying there had been "a major oversight in relation to accuracy".
The regulator has directed the BBC to air a evening statement about its findings.
"As this represents a significant violation of our regulations, we are instructing the corporation to broadcast a announcement of our findings against it on BBC Two at 21:00, with a schedule to be finalised," the statement read.
'Risk to Erode Trust'
The authority's announcement stated: "Our investigation determined that the documentary's failure to disclose that the voice's parent held a post in the Hamas-controlled government was significantly deceptive.
"This implied that the viewers did not have critical information which may have been highly relevant to their judgment of the voice and the details he presented.
"Trust is at the heart of the relationship between a television network and its public, particularly for a national broadcasting corporation such as the BBC.
"This failing had the potential to undermine the very considerable amounts of credibility that audiences would have put in a factual film from the broadcaster about the Gaza conflict."
The programme was pulled from the BBC's streaming service in last February after the narrator's familial connections emerged, and in this past July an broadcaster's internal assessment determined it breached the broadcaster's editorial guidelines on factual correctness.
A corporation official commented: "The regulator's decision is in line with the findings of the corporation's inquiry, that there was a serious error in the programme in relation to the broadcaster's journalistic policies on factual correctness, which aligns with Rule 2.2 of the authority's broadcasting regulations.
"We have apologised for this and we comply with Ofcom's decision in complete. We will adhere to the sanction as soon as the date and language are finalised."
