Wikipedia will encrypt all connections with Britain if new laws to track internet, text and email communications are implemented.
Jimmy Wales, founder of the online encyclopaedia, said that the "snooper's charter" would be a disaster for British communications.
He likened the law to measures more usually taken in restrictive regimes such as China or Iran, and said that if UK ISPs are forced to keep track of users' movements Wikipedia will encrypt their connections.
Giving evidence to MPs on the Draft Communications Data Bill, Wales said:
"If we find that UK ISPs are mandated to keep track of every single web page that you read at Wikipedia, I am almost certain we would immediately move to a default of encrypting all communication to the UK, so that the local ISP would only be able to see that you are speaking to Wikipedia, not what you are reading.
"That kind of response for us to do is not difficult. We don’t do it today because there doesn’t seem to be a dramatic need for it or any dramatic threat to our customers, but it’s something that I think we would do, absolutely."
He said encryption would force the government to "hack" citizens' web movements, and that "doesn’t sound like something a civilised democracy wants to be involved with".
He added: "It’s more like something I would expect from the Iranians or the Chinese, frankly."