China's Uighur population living in the restive western Xinjiang province, are ethnically distinct from the country's majority Han population.
Recent years have seen bloody clashes in the region, which the Chinese government blames on extremists and separatists.
Rights groups, however, say the unrest is more a reaction to repressive policies, and argue that the new measures may end up pushing some Uighurs into extremism.
Although the Chinese government recognizes 56 different ethnic minorities - including Uighurs - in the country, they have tried to crack down on expressions of individuality to create a homogenous society under Communism.
In late June, the Education Department in Hotan province [Hetian in Chinese] issued a five-point directive which forbade teaching in the Uighur language in schools.
Schools must "insist on fully popularizing the national common language and writing system according to law, and add the education of ethnic language under the bilingual education basic principle", Radio Free Asia reported.
It said schools must ban the use of Uighur language in "collective activities, public activities and management work of the education system" and "resolutely correct the flawed method of providing Uighur language training to Chinese language teachers".
When children go back to school in the autumn, it said that Mandarin "must be resolutely and fully implemented" for the three years of preschool, and then "promoted" from the first years of elementary and middle school "in order to realize the full coverage of the common language and writing system education."
It warned that any school which "plays politics" and refuses to implement the edict will be accused of being "two-faced" and shall be "severely punished".
The national government in Beijing says it is attempting to introduce a "bilingual system" in the region's schools to facilitate the dual use of both Mandarin and Uighur, but in practice schools in the region are being forced to be monolingual.
Ilshat Hassan, the president of the US-based Uighur American Association, said the regional government was breaking China's own laws on the respect of ethnic minorities.
Under Articles 10 and 37 of the Chinese constitution, ethnic minorities have a right to preserve their own languages and traditions and students are supposed to be able "where possible [to] use textbooks in their own languages and use these languages as a media of instruction".
Hassan said the new policy is designed to "eradicate one of the most ancient Turkic languages in the world."
He said: "By enforcing this new policy at the preschool level, the Chinese government intends to kill the Uighur language at the cradle. It is nothing short of cultural genocide. The international community must not allow China to destroy our beautiful language and culture, which has thrived for several millennia."
Source: News Agencies, Edited by website team