A Singaporean casts a vote at a polling station for the country's general election in Singapore on July 10, 2020.(Xinhua)

A grandson of Singapore's founding leader Lee Kuan Yew and nephew of the current prime minister was convicted Wednesday of contempt of court over a Facebook post criticizing the judiciary during a bitter family feud.

Li Shengwu, an academic at Harvard University, was also fined S$15,000 ($11,000) by the High Court over the 2017 post in which he described the Singapore government as "very litigious and has a pliant court system."

He will have to serve a week's jail if he does not pay, Justice Kannan Ramesh said in the judgment, although Li is currently living in the US.

Li is the eldest son of business executive Lee Hsien Yang, who has been at loggerheads with his brother, Prime Minister Lee Hsien Loong, over their father's legacy.

He made the Facebook post as the family feud raged publicly following the death of the Lee "patriarch" in 2015. The spat pitted his father and aunt against his prime minister uncle.

The Attorney-General's Chambers had described his post as "an egregious and baseless attack on the Singapore Judiciary" and lodged contempt proceedings against him.

Li initially took part in the proceedings through his lawyers, but withdrew later.

"I disagree with the judgment," Li said in a Facebook post Wednesday after learning about the court's decision.

He said he was worried that the verdict would reinforce the ruling People's Action Party's "tendency to suppress ordinary political speech" in the city-state.

The PAP was returned to power in elections earlier in July although with a sharply reduced share of the popular vote and with the opposition gaining more seats in parliament.

Li's father Lee Hsien Yang joined an opposition party before the polls and campaigned for its candidates although he did not run.