President Barack Obama has been speaking to China about the importance of an open internet, stressing that social-networking sites like Twitter should not be restricted in the country.

Speaking to students in Shanghai, Obama did admit that he didn't use Twitter himself – although there is an official, verified account in his name – but said "I'm an advocate of technology and not restricting internet access."

Unrestricted access

Since March this year, access to Facebook has been restricted in China and Twitter use was stopped in the country back in July.

Obama's speech continued with him saying: "I can tell you that in the United States, the fact that we have unrestricted internet access is a source of strength and I think should be encouraged."

Although Twitter has become more known for being a playground for celebrities of late, its benefits were plain to see in the Iran elections, when the site highlighted the plight of Iran protesters in a country that seemingly advocates web censorship.