"We apologize for any upset this advert has caused — this was by no means an intention of ours," a McDonald's rep told CNBC.
The campaign stirred up a storm on social media after being aired earlier this week, with viewers calling it "disgusting" and "offensive."
The advert implies that the boy had little in common with his deceased father other than their shared enjoyment of McDonald's.
Other viewers claimed that the advert was misleading, saying they thought it was a charity advert.
Charity campaigners also responded with criticism, describing the advert as exploitative.
U.K. bereavement charity Grief Encounter told the BBC that it had received "countless calls" from upset viewers who had been affected by the advert.
"McDonald's have attempted to speak to their audience via an emotionally driven TV campaign," the charity's founder and president Dr. Shelley Gilbert told the BBC.
"However, what they have done is exploit childhood bereavement as a way to connect with young people and surviving parents alike — unsuccessfully.
"Trying to insinuate that a brand can cure all ills with one meal is insensitive and shouldn't be a way to show that a brand recognises 'the big moments in life.'"
The U.K.'s advertising regulator, the Advertising Standards Authority, said it had received complaints about the advert and would be assessing whether there were grounds for further investigation.
The advertising gaffe is the latest to tarnish the industry and follows the likes of Pepsi, which suffered a global backlash following its recent drinks campaign.
- Update: McDonald's has since withdrawn the advert, as of Wednesday May 17.
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