China's top law-making body has unveiled plans to ensure only "patriots" can govern Hong Kong, as Beijing tightens its grip on the city with changes to the electoral system. Premier Li Keqiang, addressing the National People's Congress (NPC), warned the world not to interfere. The move follows the imposition of a tough security law. Critics say Beijing is crushing dissent and removing the "one country, two systems" agreement it made with the UK. Under the agreement, Hong Kong, a former British colony, was allowed to continue with its own legal system and have rights including free speech and freedom of the press. Lord Chris Patten, former governor of Hong Kong, said China's Communist Party had "taken the biggest step so far to obliterate Hong Kong's freedoms and aspirations for greater democracy under the rule of law". The EU has warned that it may take "additional steps" over the plans announced on Friday. It called on Beijing to "carefully consider the political and economic implications on any decision to reform the electoral system of Hong Kong that would undermine fundamental freedoms, political pluralism and democratic principles". Fears that Hong Kong's "one country, two systems model" was being eroded led to huge pro-democracy protests in 2019. Some turned violent and Beijing imposed the National Security Law, which it said would target "sedition" and bring stability. Thousands of lawmakers have gathered for the annual NPC meeting in Beijing. The rubber-stamp parliament is expected to also discuss and approve economic growth targets and environmental policies from the central government.