A sweeping new law aimed at promoting ethnic unity across China came into force on Wednesday, drawing immediate condemnation from human rights organisations, the United Nations, Taiwan and members of the United States Congress, who argue it will entrench the forced assimilation of minority communities and extend Beijing's reach over critics living abroad.

The Law on Promoting Ethnic Unity and Progress was passed in March by China's National People's Congress with an overwhelming majority. Beijing says the legislation is designed to foster social cohesion, a "shared" national identity and what it calls ethnic harmony. In practice, critics say, it formalises and makes permanent a set of policies that have long been tightening restrictions on China's minority populations. The country officially recognises 56 ethnic groups; the Han Chinese are by far the largest, with the remaining 55 groups together making up just under nine percent of the population. Among the most affected are Uyghurs in the northwestern region of Xinjiang and Tibetans — communities Beijing has faced sustained international criticism over for years. The law reinforces Mandarin as the sole language of education, meaning children from the age of three may only be taught in Mandarin rather than in Tibetan, Uyghur or other minority languages. Reports gathered by rights groups describe authorities visiting families who teach children their native tongue at home, and neighbours informing on one another for speaking languages other than Mandarin.

Amnesty International's deputy regional director, Sarah Brooks, said the law demands "political and ideological alignment with the Chinese Communist Party" and will "further institutionalise policies of forced assimilation," pushing groups such as Uyghurs, Tibetans and Mongols to "adopt a single, state-defined national identity dominated by Han Chinese culture." UN human rights chief Volker Türk has called for the law to be repealed, warning it risks deepening restrictions on freedoms of language, education, religion, culture, expression and assembly. Researchers note that while many of the measures are not new — Inner Mongolia, for instance, has already banned Mongolian from schools — the law makes them legally permanent. Yalkun Uluyol, a China researcher at Human Rights Watch, has noted that the law also affects the Chinese diaspora, reflecting Beijing's longstanding practice of pressuring overseas nationals or their relatives when it considers them a threat.

A particularly contentious element of the legislation is a clause asserting jurisdiction beyond China's borders: individuals or organisations anywhere in the world can be held legally responsible under Chinese law if deemed to be "undermining ethnic unity and progress or inciting ethnic separatism." Taiwan's government expressed "strong condemnation," warning that its citizens — who already face significant risks when travelling to mainland China — now faced "yet another law to fabricate charges." Nine US senators, spanning both major parties, pledged to continue opposing what they called Beijing's attempt to "legitimise its transnational repression." A Chinese vice-minister of justice defended the extraterritorial clause as "legitimate, lawful and necessary," while Beijing reiterated its standard position that its policies benefit all ethnic groups through security and economic development.

The law matters beyond China's borders because it signals a further hardening of the state's approach to diversity at a moment of heightened geopolitical tension. Analysts suggest Beijing views ethnic diversity as a potential source of instability that foreign powers — particularly the United States — could exploit. For minority communities inside China, the immediate consequences are concrete: the criminalisation of cultural, religious and linguistic expression that differs from the Han-dominated national identity the state is seeking to construct. For the international community, the extraterritorial clause raises the prospect of Chinese pressure being applied to activists, academics and diaspora members in countries with no treaty obligation to act on Beijing's behalf — a dynamic already visible in cases such as the arrest of a Chinese student in France who had promoted the Tibetan language, and an intimidation campaign that halted research into Uyghur forced labour at a British university.