The British broadcaster engaged in a "major breach" of broadcasting rules by not revealing that the presenter of a film about the Gaza situation was the child of a Hamas administrator, as ruled by UK media regulator Ofcom.
An probe by the media regulator 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, saying there had been "a major oversight in relation to truthfulness".
Ofcom has directed the corporation to air a evening announcement about its conclusions.
"Since this amounts to a serious breach of our regulations, we are instructing the corporation to air a message of our conclusions against it on BBC Two at nine o'clock in the evening, with a schedule to be determined," the statement read.
'Potential to Erode Trust'
The watchdog's report declared: "Our probe found that the documentary's lack of disclosure that the presenter's father served in a position in the Hamas-administered administration was substantially inaccurate.
"Consequently that the viewers did not have essential details which may have been highly relevant to their judgment of the presenter and the information he shared.
"Confidence is at the heart of the relationship between a broadcaster and its viewers, particularly for a state-funded media outlet such as the BBC.
"This error had the potential to damage the significantly high levels of trust that the public would have placed in a BBC factual programme about the conflict in Gaza."
The documentary was pulled from the online platform in last February after the presenter's familial connections came to light, and in the month of July an internal BBC review determined it infringed the broadcaster's journalistic standards on factual correctness.
A corporation official commented: "The authority's determination is in agreement with the conclusions of the internal assessment, that there was a significant failing in the programme in relation to the BBC's Editorial Guidelines on truthfulness, which reflects Rule 2.2 of Ofcom's Broadcasting Code.
"We expressed regret for this and we comply with the authority's determination in complete. We will comply with the penalty as soon as the schedule and wording are finalised."
