Authorities added another 8 months to Tsongon Tsering’s sentence.
He was frequently detained by authorities for songs that were critical of Chinese policies, sources say.
The move comes amid growing concerns China’s opposition to the Tibetan spiritual leader’s activities.
Tibetan and Uyghur advocacy groups will need to work harder for support from the international community.
The two leaders spoke to reporters after Thursday’s meeting at the White House.
A recent study suggests Tibetans, Uyghurs in Switzerland face surveillance and cyberattacks initiated by Beijing.
The major religious center has suffered demolitions and authorities have forced clergy to leave.
Gyalo Thondup, 97, who played a key role in Tibet, died on Feb. 8.
In his last interview before his death, the Dalai Lama’s brother assessed his role in the CIA-backed campaign
Sam Brownback warns Beijing about interfering in the Dalai Lama’s succession.
