Taiwanese human rights activists are calling on President Donald Trump to ask for the release of a man charged with political crimes in China during his visit to Beijing this week.

The activists said Tuesday that Trump should raise the case of Taiwanese human rights activist Lee Ming-che when meeting Chinese President Xi Jinping.

The 42-year-old disappeared on a trip to China in March and showed up at a court hearing in the southern city of Changsha in September. Supporters in Taiwan say he was forced to plead guilty.

Lee's case has strained already stalemated relations between political rivals China and Taiwan.

In June the U.S. Congressional Executive Commission on China added Lee to a database of people it considers political prisoners.

Trump arrives in Beijing on Wednesday.