The BBC engaged in a "major breach" of media regulations by omitting to mention that the voice of a programme about the Gaza conflict was the son of a Hamas official, as determined by UK media regulator Ofcom.
An investigation by Ofcom into Gaza: How to Survive a Warzone has determined that the film was "materially misleading".
The chief executive of the broadcaster had earlier expressed regret, saying there had been "a serious error in relation to factual correctness".
Ofcom has instructed the BBC to broadcast a peak-time declaration about its decisions.
"As this represents a serious breach of our code, we are instructing the broadcaster to transmit a statement of our findings against it on BBC Two at 21:00, with a timing to be determined," it said.
'Risk to Undermine Credibility'
The regulator's report said: "Our probe determined that the film's failure to disclose that the voice's father served in a role in the Hamas-run administration was materially misleading.
"It meant that the viewers did not have vital facts which may have been highly relevant to their evaluation of the presenter and the details he provided.
"Trust is at the core of the connection between a television network and its public, particularly for a national broadcasting corporation such as the BBC.
"This failing had the possibility to undermine the significantly high degrees of trust that audiences would have invested in a factual film from the broadcaster about the conflict in Gaza."
The documentary was removed from the BBC's streaming service in last February after the presenter's personal associations came to light, and in July an broadcaster's internal assessment determined it violated the broadcaster's editorial guidelines on accuracy.
A representative for the broadcaster stated: "The regulator's decision is in line with the results of the internal assessment, that there was a major oversight in the documentary in relation to the corporation's content standards on factual correctness, which reflects clause 2.2 of the authority's broadcasting regulations.
"We issued an apology for this and we accept the authority's determination in its entirety. We will comply with the directive as soon as the timing and language are finalised."
