China's Communist Party congress begins in Beijing
China's biggest political event, the Communist Party congress, has begun in Beijing under tight security.
Chinese President Xi Jinping addressed more than 2,000 delegates in the capital for more than three hours.
The closed-door summit, which takes place once every five years, determines who rules China and the country's direction for the next term.
Mr Xi, who became the leader in 2012, has been consolidating power and is expected to remain as party chief.
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The congress, which also decides on a roadmap for China for the next five years, is expected to finish next week.
Shortly after the congress ends, the party is expected to unveil the new members of China's top decision-making body, the Politburo Standing Committee, who will steer the country.
In his speech, Mr Xi listed China's recent achievements, saying that "socialism with Chinese characteristics in this new era" meant China had "become a great power in the world", and added that the country should not copy foreign political systems.
- Briefly described a two-stage plan for China's "socialist modernisation", to be achieved by 2050
- Warned against separatism – in an apparent reference to movements in Xinjiang, Tibet and Hong Kong – and reiterated the government's principle that Taiwan is part of China
- Said China "would not close its doors to the world" and promised further economic reform, including lowering barriers for foreign investors
'Surging ideological confidence'
Analysis by Carrie Gracie, BBC China editor
Xi Jinping is a much more assertive leader than his predecessors. In a long and confident speech, he looked back on his first five years in office, saying the party had achieved miracles and China's international standing had grown.
But the most striking thing in his mission statement was ideological confidence. Recently Party media have talked of crisis and chaos in western democracies compared to strength and unity in China.
Today Xi Jinping said he would not copy foreign political systems and that the communist party must oppose anything that would undermine its leadership of China.
Mr Xi also mentioned his wide-reaching corruption crackdown within the Party that has punished more than a million officials, report BBC correspondents in Beijing.
Beijing is decked out in welcome banners and festive displays for the congress.
However, the capital is also on high alert. Long lines were seen earlier this week at railway stations due to additional checks at transport hubs.
The congress has also affected businesses, with some restaurants, gyms, nightclubs and karaoke bars reportedly shutting down due to tightened security rules.
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An austerity drive, instituted by Mr Xi, has meant a more pared down congress, with Chinese reports this week of delegates' hotels cutting back on frills such as decorations, free fruit in rooms and lavish meals.
Meanwhile, state media have said the Party is expected to rewrite its constitution to include Mr Xi's "work report" or political thoughts, which would elevate him to the status of previous Party giants Mao Zedong and Deng Xiaoping.
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Some see Mr Xi as accruing more power than any leader since Mao, and the congress will be watched closely for clues on how much control now rests in the hands of just one man, says the BBC's John Sudworth.
Since becoming president, Mr Xi has tightened control within the Party and also in Chinese society, with increasing censorship and arrests of lawyers and activists.
Under Mr Xi, China's modernisation and reform has also accelerated, as has its assertiveness on the world stage.
He continues to enjoy widespread support among ordinary citizens in China.