The new directive prohibits use of the language in schools up to and including the secondary level in Hotan prefecture.
Dolkun Isa was stopped at the Italian Senate, where he was to speak on Uyghur issues.
Meanwhile, nearly 100 Uyghurs are being held by Egypt’s national intelligence service.
Hezritieli Memet has been held since February, when his parents were taken into custody.
Reports suggest the more than 200 Uyghurs are being interrogated ahead of deportation to China.
Non-Hans in Xinjiang’s capital are rated by 10 categories, including whether they are Uyghur.
University leaders meanwhile meet with official Chinese delegations, deny anyone detained 'on campus.'
The death of ethnic Kazakh imam Akmet in police custody is officially blamed on suicide, but those who supported him are being rounded up.
Fearful Uyghurs scramble to get out of Egypt and avoid forced return to China, where they risk torture and arbitrary jailing.
Many are seized while trying to flee to Turkey, while others go into hiding to evade police, sources say.
Many detainees face charges of "illegal religious activities" after they traveled overseas on pilgrimage, while others face "extremism" charges.