Russell Crowe has launched his Depression-era film Cinderella Man at the Venice Film Festival saying the US cannot take its wealth for granted.
Zellweger and Crowe play husband and wife in Cinderella Man
Crowe, 41, who plays boxer Jim Braddock and Renee Zellweger who plays his wife, both attended the European premiere.
He said: "A really important part of making this film is to remind America that the current abundance they are experiencing is not an absolute right."
The film got a lukewarm reception when it was released in the US in June.
It was also overshadowed by the Gladiator star's arrest after he allegedly threw a telephone at a porter in a New York hotel.
Reporters at the Cinderella Man press conference were told their microphones would be shut off if they asked any questions about the incident.
Crowe, who plays a father in the film, said he personally found fatherhood "the most illuminating and fantastic experience of my life".
"It's a thing I would recommend to everybody," he said.
The actor and his wife Danielle Spencer have a 20-month-old son named Charlie.
Zellweger, who plays Crowe's wife in the film, said it had been "wonderful" to play "a married couple who are unconditionally supportive to one another".
However, the Bridget Jones actress refused to make any parallels with her own four-month marriage to country singer Kenny Chesney.