The BBC engaged in a "major breach" of media regulations by failing to disclose that the presenter of a documentary about the Gaza conflict was the child of a Hamas representative, according to regulatory body Ofcom.
An inquiry by the broadcasting watchdog into Gaza: How to Survive a Warzone has concluded that the programme was "materially misleading".
The BBC's director general had already issued an apology, saying there had been "a serious error in relation to truthfulness".
Ofcom has directed the corporation to broadcast a evening declaration about its decisions.
"Given this constitutes a significant violation of our rules, we are directing the broadcaster to broadcast a message of our findings against it on BBC2 at 21:00, with a timing to be finalised," it said.
'Potential to Damage Credibility'
The regulator's statement said: "Our probe determined that the documentary's failure to disclose that the narrator's male guardian held a position in the Hamas-run government was significantly deceptive.
"It meant that the audience did not have essential details which may have been highly relevant to their evaluation of the narrator and the information he shared.
"Credibility is at the heart of the bond between a television network and its audience, especially for a national broadcasting corporation such as the British Broadcasting Corporation.
"This failing had the potential to damage the very considerable levels of credibility that the public would have placed in a factual film from the broadcaster about the Gaza conflict."
The programme was withdrawn from the online platform in last February after the boy's family links emerged, and in the month of July an corporation's own inquiry concluded it violated the organization's content policies on truthfulness.
A BBC spokesperson stated: "The Ofcom ruling is in accordance with the results of the internal assessment, that there was a significant failing in the programme in relation to the corporation's content standards on truthfulness, which corresponds to clause 2.2 of the authority's broadcasting regulations.
"We have apologised for this and we comply with the authority's determination in its entirety. We will comply with the directive as soon as the timing and wording are finalised."
