Prime Minister David Cameron has unveiled plans to block encrypted communications in the UK.

In a speech, Cameron said it was important to establish “the right legal framework to intercept the communications of potential terrorists,” following the recent attacks in Paris. He said that government agencies should have access not only to communications data like call records, but also the content of those communications.

If the Conservative Party are still in power following this years general election, Cameron said he intends to introduce legislation in 2016 that would outlaw messaging apps which encrypt users communications, such as WhatsApp and Snapchat.

“I have very simple principle to apply here, which should be at the heart of the legislation which will be necessary,” said Cameron. “That is: in our country, do we want to allow a means of communication between people, which even in extremis, with a signed warrant from the Home Secretary personally, that we cannot read?”

The plans have already attracted plenty of criticism online. BoingBoings Cory Doctorow points out that, as these proposals would mean creating a backdoor that can be used by government agencies, software would be made vulnerable for criminal access and attacks, through this same backdoor.

The legislation could also interfere with any banking or shopping app which uses secure protocols to protect users payment details – and even, if the plans are followed to their logical conclusion, any software developed outside of the UK.