A prominent political activist for China's Uyghur ethnic minority, Rebiya Kadeer, will be allowed into Japan during next week's Group of 20 leaders' summit, her supporters said Friday.

Japanese government sources confirmed that Tokyo has issued a visa to Kadeer despite calls not to do so from Beijing. She plans to protest human rights violations by the Chinese government during her stay, which will coincide with President Xi Jinping's visit to Osaka to participate in the summit.

Roughly 10 million Uyghurs live in China, mainly in the far-western Xinjiang autonomous region. The Chinese government has been criticized for its oppressive treatment of the majority-Muslim group, including sending large numbers to mass detention camps for "re-education."

President of the Free Indo-Pacific Alliance, a group that represents exiled minorities including Tibetans, Kadeer herself fled China after being labeled a separatist and now lives in the United States.

The visa was applied for on June 7 and issued Wednesday on the grounds Kadeer had already traveled to Japan more than 10 times, and that there was no legal reason to keep her from doing so again, the government sources said.

Kadeer's supporters said the process was longer than for previous visas, which only took a week or so to be issued.

According to the government sources, Beijing asked Tokyo in December to handle the matter of Kadeer's entry into Japan during Xi's visit "appropriately." The request was made directly to the office of Prime Minister Shinzo Abe via a senior official from China's Ministry of State Security, they said.