Directed by Martin Scorsese, the 30-second TV spot has been running in the US, as well as the UK, since November. It follows De Niro walking through his home city of New York, in black and white, with the actor providing a voiceover celebrating "his" city.
He utters phrases such as "My East … my West Side" over a montage of scenes of the city from Chinatown to Little Italy. A shot of Ground Zero is matched to "My heartbreak".
He ends by saying "My life happens here... My card is American Express" as the tagline appears on the screen "My life. My card".
Newspapers around the world have seized on internet forums criticism of the ad, quoting a member of the Digital Spy site, who wrote: "For a guy who is supposed to love the city, you'd think he'd show a bit more class... Using a tragedy to sell a product stinks."
The debate about the sensitivity of the commercial has coincided with the panning of De Niro's latest movie, a thriller called 'Hide and Seek'.
De Niro had not made a commercial for over 30 years until he agreed to work for American Express because the card company has funded his New York TriBeca film festival since 2002. A shot of a cinema marquee promoting the film festival appears in the ad.
Other brands that have played on associations with De Niro have included Volkswagen, which set up a movie icon website linked to a De Niro film season for the 30th anniversary of the Golf.
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