The BBC committed a "major breach" of media regulations by not revealing that the voice of a programme about the Gaza conflict was the offspring of a Hamas official, as ruled by British broadcasting authority Ofcom.
An inquiry by the media regulator into the programme Gaza: How to Survive a Warzone has found that the programme was "materially misleading".
The chief executive of the broadcaster had already issued an apology, stating there had been "a major oversight in relation to factual correctness".
Ofcom has ordered the corporation to broadcast a peak-time declaration about its findings.
"Given this constitutes a serious breach of our code, we are ordering the broadcaster to broadcast a message of our determinations against it on the BBC's second channel at nine o'clock in the evening, with a timing to be determined," the statement read.
'Possibility to Erode Credibility'
The regulator's announcement said: "Our probe determined that the documentary's omission to reveal that the voice's male guardian occupied a post in the Hamas-administered government was significantly deceptive.
"It meant that the audience did not have vital facts which may have been extremely pertinent to their assessment of the presenter and the content he presented.
"Trust is at the heart of the relationship between a broadcaster and its viewers, notably for a national broadcasting corporation such as the British Broadcasting Corporation.
"This oversight had the potential to damage the exceptionally strong degrees of confidence that the public would have put in a factual film from the broadcaster about the conflict in Gaza."
The documentary was withdrawn from the BBC's streaming service in the month of February after the boy's familial connections came to light, and in the month of July an internal BBC review concluded it breached the corporation's journalistic standards on truthfulness.
A BBC spokesperson commented: "The authority's determination is in agreement with the findings of Peter Johnston's review, that there was a significant failing in the programme in relation to the BBC's Editorial Guidelines on factual correctness, which aligns with regulation 2.2 of the regulator's media standards.
"We have apologised for this and we comply with the authority's determination in its entirety. We will comply with the sanction as soon as the date and language are determined."
