In a speech aimed largely at the Trump administration in the US, President Xi said there could be no winner in any trade war.
He believed the countries taking part in the summit - China, Russia, India, Brazil and South Africa - should be resolute against closed-door protectionism.
A unified voice
The BRICS group comprises more than 40 per cent of the global population.
Analysts say its members have struggled to find a unified voice, but their common opposition to US trade policy could help to galvanise them.
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