Speaking at a conference in London, Schmidt recalled a meeting with President Xi Jinping and Premier Li Keqiang in November 2013, just weeks after China passed tough regulations on social media. Under new laws, people face harsh penalties if libellous "online rumours" they create are reposted more than 500 times.

"The most interesting thing about talking to the government, from the president all the way to the governors, is that they are obsessed with the Internet, which is why they passed these laws," Schmidt told the conference, which was organized by independent policy institution Chatham House.

He did not elaborate on their conversations.

Google in 2010 moved its Chinese search engine service out of China, the world's No 2 economy, citing rampant censorship, and now operates it from Hong Kong.

But the growing popularity of services like Weibo, a microblogging service that is China's version of Twitter, and instant messaging site WeChat will make censorship increasingly difficult, Schmidt said.

"You simply cannot imprison enough Chinese people when they all agree to something," he said. "You won't be able to stop it even if you don't like it, and it will cause liberalization."


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