The public service broadcaster committed a "serious breach" of media regulations by not revealing that the narrator of a documentary about the Gaza conflict was the son of a Hamas administrator, as ruled by British broadcasting authority Ofcom.
An probe by Ofcom into the programme Gaza: How to Survive a Warzone has concluded that the programme was "substantially inaccurate".
The head of the BBC had already issued an apology, noting there had been "a significant failing in relation to factual correctness".
The regulator has directed the BBC to broadcast a evening announcement about its findings.
"Since this amounts to a major infringement of our code, we are ordering the broadcaster to air a announcement of our determinations against it on the BBC's second channel at 21:00, with a date to be finalised," the regulator stated.
'Potential to Erode Confidence'
The regulator's announcement said: "The inquiry we conducted found that the programme's failure to disclose that the presenter's male guardian occupied a post in the Hamas-controlled authority was substantially inaccurate.
"This implied that the viewers did not have vital facts which may have been highly relevant to their judgment of the voice and the content he shared.
"Confidence is at the core of the connection between a broadcaster and its audience, particularly for a national broadcasting corporation such as the public broadcaster.
"This error had the potential to erode the exceptionally strong levels of trust that viewers would have placed in a documentary produced by the BBC about the Israel-Gaza war."
The programme was removed from the BBC's streaming service in February after the presenter's familial connections came to light, and in the month of July an internal BBC review concluded it infringed the corporation's journalistic standards on accuracy.
A representative for the broadcaster commented: "The authority's determination is in accordance with the findings of Peter Johnston's review, that there was a significant failing in the programme in relation to the corporation's content standards on factual correctness, which corresponds to Rule 2.2 of the regulator's media standards.
"We have apologised for this and we accept Ofcom's decision in complete. We will comply with the sanction as soon as the date and wording are confirmed."
