The British broadcaster committed a "significant breach" of media regulations by omitting to mention that the presenter of a programme about the Gaza situation was the child of a Hamas official, as ruled by UK media regulator Ofcom.
An probe by the broadcasting watchdog into the programme Gaza: How to Survive a Warzone has concluded that the documentary was "materially misleading".
The BBC's director general had earlier expressed regret, saying there had been "a major oversight in relation to accuracy".
Ofcom has instructed the BBC to transmit a evening announcement about its decisions.
"As this represents a serious breach of our regulations, we are ordering the broadcaster to transmit a announcement of our determinations against it on the BBC's second channel at nine o'clock in the evening, with a timing to be determined," it said.
'Risk to Erode Trust'
The regulator's report stated: "Our probe determined that the film's failure to disclose that the presenter's father held a role in the Hamas-controlled authority was substantially inaccurate.
"This implied that the audience did not have vital facts which may have been very significant to their evaluation of the presenter and the information he presented.
"Confidence is at the center of the bond between a broadcaster and its viewers, notably for a public service broadcaster such as the public broadcaster.
"This oversight had the possibility to erode the very considerable degrees of confidence that the public would have placed in a documentary produced by the BBC about the Israel-Gaza war."
The documentary was removed from the BBC's streaming service in February after the presenter's family links were revealed, and in this past July an internal BBC review found it infringed the broadcaster's editorial guidelines on truthfulness.
A BBC spokesperson said: "The authority's determination is in agreement with the conclusions of the corporation's inquiry, that there was a serious error in the documentary in relation to the BBC's Editorial Guidelines on truthfulness, which corresponds to Rule 2.2 of the authority's broadcasting regulations.
"We have apologised for this and we agree with Ofcom's decision in its entirety. We will comply with the penalty as soon as the timing and wording are finalised."
