Britain is working to push through new laws that will effectively ban the use of strong encryption in the country, forcing companies to provide unscrambled content if served with a court warrant.

The government's new Investigative Powers Bill proposes to make tech companies such as Apple and Google retain decryption keys for encrypted devices and services.

Baroness Joanna Shields, the Conservative UK minister of internet security and a former executive with Google, Facebook and RealNetworks, said there was no intention by the government to weaken encryption or provide backdoors.

The move comes despite an election promise by prime minister David Cameron in January to ban communications the government could not read.

Shields denied Cameron advocated banning encryption, claming the government was worried about companies building "end-to-end encrypted applications and services and not retaining the keys [to them]".

"The prime minister has repeatedly said that there cannot be a safe place for terrorists, criminals and paedophiles to operate freely, with impunity and beyond the reach of law," she said.

"This is not about creating backdoors; this is about companies being able to access communications on their network when presented with a warrant."

Shields claimed there had been an "alarming movement towards end-to-end encrypted applications" and that it was essential the companies building such technology are able to decrypt that information and provide it to law enforcement.

When the Investigatory Powers Bill becomes law, internet providers and companies will also be required to retain users' web browsing histories for a year for law enforcement purposes.

Following revelations by former United States National Security Agency (NSA) contractor Edward Snowden, Apple and Google decided last year to do away with the ability to decrypt customer devices and not retain the keys.

Apple is currently embroiled in a court case in the United States where it is arguing it has no ability to decrypt newer iDevices.

Its stance is being challenged by the country's Department of Justice, which insists the company must be able to decrypt the devices if required to by law enforcement.