Apple is taking the unprecedented step of removing its highest level data security tool from customers in the UK, after the government demanded access to user data.

Advanced Data Protection (ADP) means only account holders can view items such as photos or documents they have stored online through a process known as end-to-end encryption.

But earlier this month the UK government asked for the right to see the data, which currently not even Apple can access.

Apple did not comment at the time but has consistently opposed creating a “backdoor” in its encryption service, arguing that if it did so, it would only be a matter of time before bad actors also found a way in.

Now the tech giant has decided it will no longer be possible to activate ADP in the UK.

It means eventually not all UK customer data stored on iCloud – Apple’s cloud storage service – will be fully encrypted.

Data with standard encryption is accessible by Apple and shareable with law enforcement, if they have a warrant.

The Home Office told the BBC: “We do not comment on operational matters, including for example confirming or denying the existence of any such notices.”

In a statement Apple said it was “gravely disappointed” that the security feature would no longer be available to British customers.

“As we have said many times before, we have never built a backdoor or master key to any of our products, and we never will,” it continued.

• How does encryption work?

The ADP service is opt-in, meaning people have to sign up to get the protection it provides.

From 1500GMT on Friday, any Apple user in the UK attempting to turn it on has been met with an error message.

Existing users’ access will be disabled at a later date.

It is not known how many people have signed up for ADP since it became availabl