Uighur rights activist Rebiya Kadeer on Wednesday sought help from Japanese politicians to request China to release prisoners and dispatch an investigating team.
Kadeer's visit to Japan has already drawn criticism from China since Beijing considers the ethnic minority representative one of the masterminds behind the July 5 disturbances in the Xinjiang Uighur Autonomous Region.
Japan, however, thinks Kadeer's visit should not negatively affect bilateral relations because she was invited by a private organisation, Chief Cabinet Secretary Takeo Kawamura said Wednesday.
After the meeting with Liberal Democratic Party (LDP) members, Kadeer said she was hopeful of cooperation from Tokyo.
"I received the impression that they will not accept China's continued oppression of the Uighurs," Kyodo News Agency quoted the activist as saying.
An LDP lawmaker said the minority issue in China is something "that cannot be left untouched" and added that the party members planned to report on the meeting to the government.
Nearly 200 people died in violent clashes between Uighur-minority Muslims and police and Han Chinese residents of the Xinjiang capital of Urumqi in early July.