"We stand for our good intention behind this but we're also sorry if it is making some harm and we're sorry if it makes documentation or reporting in war zones more difficult," Norwegian producer John Einar Hagen told AFP.
His apology followed an outcry among Internet users, media outlets and rights organisations about the ethical implication of posting a fake video featuring children in war zones.
In the "Syrian hero boy" footage, directed by 34-year-old Norwegian director Lars Klevberg, a young boy braves sniper fire and appears to be shot while rescuing a girl hiding behind a burned car in what seems to be war-torn Syria.
After posting the film on YouTube on Monday, the director revealed on Friday it had been shot on location in Malta last summer with professional actors.
By the time the director admitted the hoax, the video had been watched more than five million times.
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Klevberg said in a statement the idea of the video was "to spur debate, urge action on behalf of innocent children all over the world who are affected by war".
Human Rights Watch said Saturday that such good intentions had been overrun by the negative consequences of the hoax.
"If the video hoax achieved any short-term goals by highlighting the plight of children in war, those have been washed away by undermining confidence in professional reporting and war crimes documentation that is done with care and consideration for the facts," HRW childrens' rights advisor Fred Abrahams said in a statement.
"By releasing a fake video, Klevberg has made it easier for war criminals to dismiss credible images of abuse."
The Syrian conflict began almost four years ago, born out of the upheaval of the Arab Spring protests.
More than 195,000 people have been killed and more than half the population has been forced to flee their homes.