The wife of China's jailed Nobel Peace Prize winner has written an open letter to new Chinese leader Xi Jinping to protest the 11-year prison term given to her brother.

In the letter, Liu Xiaobo's wife Liu Xia said the sentencing Sunday was unfair and urged Xi to govern China in a way that respects the rights of individuals and avoids "ruthless suppression based on violence."

A Beijing court had convicted the brother, Liu Hui, of fraud in a real estate dispute. Family supporters have called the case retribution for Liu Xiaobo's activism.

The letter was handwritten and signed by "citizen Liu Xia." Beijing lawyer Shang Baojun, who represented Liu Xiaobo and Liu Xia's brother, confirmed the authenticity of the letter, which he posted online.