A prominent Chinese rights activist expressed defiance on Friday after a court upheld his four-year jail sentence, saying the pall of communism and dictatorship would eventually give way to freedom and justice.

The ruling sparked fresh criticism from the United States, European Union and rights groups, though it had been expected as China's courts are controlled by the Communist Party and almost never rule in favor of dissidents.

"This ridiculous judgment cannot hold back the tide of human progress," Xu Zhiyong told the court loudly after the verdict was read out, his lawyers said.