BEIJING (NYTimes) - Chinese dissident artist Ai Weiwei was under house arrest in Beijing when he was invited to remotely direct a segment for Berlin, I Love You, an anthology film set in the German capital.

The segment portrayed the separation of a family and featured his five-year-old son, who lived in Germany. "It's sweet and has some sadness," Ai said about his segment, which he directed in 2015.

"Not politically sensitive at all."

But in the final version of the film, which was released in the United States this month, his contribution was nowhere to be found. The producers told him that investors, distributors and other partners had raised concerns about his political sensitivity in China.

Starring Keira Knightley, Helen Mirren and Luke Wilson, Berlin, I Love You is part of the Cities Of Love franchise, in which international directors are invited to make short, intersecting vignettes that take place in a particular city.

Claus Clausen, one of the film's producers who fought to keep Ai's segment, said: "Some of the distributors just told us: 'Frankly, we are not taking the movie with him in it.'

"We were really, really desperate. No matter what decision we made, we were going to lose. In the end, we were heartbroken."

Ai, who now lives in Berlin, has long been an outspoken critic of the Chinese government.

He said he had become more concerned over the years that some Western governments, companies and organisations were apparently willing to engage in self-censorship in order not to offend China.