The British broadcaster engaged in a "significant breach" of media regulations by failing to disclose that the voice of a film about the Gaza conflict was the offspring of a Hamas official, according to regulatory body Ofcom.
An investigation by the media regulator into the programme Gaza: How to Survive a Warzone has concluded that the programme was "significantly deceptive".
The chief executive of the broadcaster had previously apologised, stating there had been "a major oversight in relation to truthfulness".
Ofcom has instructed the broadcaster to air a evening statement about its conclusions.
"Since this amounts to a significant violation of our rules, we are directing the BBC to broadcast a statement of our conclusions against it on BBC Two at 9pm, with a schedule to be finalised," it said.
'Potential to Damage Trust'
The authority's report declared: "The inquiry we conducted determined that the programme's omission to reveal that the presenter's father occupied a position in the Hamas-controlled authority was significantly deceptive.
"It meant that the viewers did not have vital facts which may have been very significant to their judgment of the voice and the details he shared.
"Trust is at the core of the connection between a media organization and its public, notably for a national broadcasting corporation such as the British Broadcasting Corporation.
"This error had the risk to erode the significantly high levels of confidence that audiences would have put in a documentary produced by the BBC about the conflict in Gaza."
The film was withdrawn from the BBC's streaming service in February after the presenter's family links emerged, and in July an corporation's own inquiry found it infringed the organization's content policies on factual correctness.
A representative for the broadcaster said: "The regulator's decision is in agreement with the results of Peter Johnston's review, that there was a major oversight in the documentary in relation to the BBC's Editorial Guidelines on factual correctness, which reflects clause 2.2 of the authority's broadcasting regulations.
"We have apologised for this and we agree with Ofcom's decision in full. We will adhere to the sanction as soon as the date and wording are finalised."
