Shanghai: Chinese President Xi Jinping has used a keynote address at the Chinese International Import Expo in Shanghai to warn countries that they risk stifling innovation if they fail to remove barriers and "knowledge blockades" preventing cooperation on technology.

His comments came amid a trade war with the United States that has seen a growing list of Chinese technology companies, including China's 5G champion Huawei, hit with US restrictions.

China launched its commercial 5G services last week, but Australia has barred Huawei from its 5G network over security concerns. Britain is expected to allow the company to participate in the development of its 5G network, but that decision has been delayed until after its forthcoming election.

Top Chinese artificial intelligence companies are also facing fresh US bans on human rights grounds. But the head of a US National Security Commission panel on Artificial Intelligence (AI), former Google chief executive Eric Schmidt, said overnight that barring cooperation with Chinese researchers would harm US innovation.