The BBC engaged in a "serious breach" of media regulations by not revealing that the presenter of a documentary about the Gaza conflict was the son of a Hamas official, as determined by British broadcasting authority Ofcom.
An investigation by the media regulator into Gaza: How to Survive a Warzone has determined that the film was "substantially inaccurate".
The BBC's director general had already issued an apology, saying there had been "a significant failing in relation to factual correctness".
The authority has ordered the broadcaster to broadcast a evening announcement about its findings.
"Since this amounts to a major infringement of our code, we are instructing the broadcaster to transmit a statement of our conclusions against it on the BBC's second channel at nine o'clock in the evening, with a timing to be confirmed," the statement read.
'Risk to Undermine Trust'
The regulator's statement declared: "Our probe determined that the documentary's omission to reveal that the narrator's parent served in a role in the Hamas-administered administration was substantially inaccurate.
"Consequently that the public did not have critical information which may have been highly relevant to their assessment of the presenter and the information he presented.
"Confidence is at the core of the bond between a broadcaster and its public, notably for a public service broadcaster such as the public broadcaster.
"This oversight had the potential to erode the very considerable amounts of confidence that audiences would have put in a factual film from the broadcaster about the Gaza conflict."
The programme was removed from the BBC's streaming service in February after the presenter's family links were revealed, and in July an internal BBC review found it infringed the organization's editorial guidelines on truthfulness.
A BBC spokesperson stated: "The Ofcom ruling is in agreement with the conclusions of the corporation's inquiry, that there was a significant failing in the documentary in relation to the BBC's Editorial Guidelines on accuracy, which corresponds to regulation 2.2 of Ofcom's Broadcasting Code.
"We issued an apology for this and we comply with the regulator's ruling in its entirety. We will follow the directive as soon as the schedule and language are determined."
