Apple's appeal against a UK government demand to be able to access its customers' most highly encrypted data is set to be considered at a secret hearing at the High Court on Friday, according to a BBC report.

It is due to be considered by the Investigatory Powers Tribunal - an independent court which has the power to investigate claims against the UK intelligence services.

The US tech giant took legal action earlier this month in response to the Home Office's demand for the right to access customer information protected by Apple's Advanced Data Protection (ADP) programme.

Currently Apple cannot access data stored in this way and therefore is unable to share it with law enforcement if issued with a warrant.

The government says it needs to be able to see it if there is a national security risk.

The US tech giant took legal action earlier this month in response to the Home Office's demand for the right to access customer information protected by Apple's Advanced Data Protection (ADP) programme.

The hearing is due to be held in private because it relates to the security services, but campaigners say the public has a right to hear it.

The row began in February when it first emerged the government was seeking the right to be able to access data protected by ADP, using powers granted to it under the Investigatory Powers Act.

The Act allows it to covertly compel firms to provide information to law enforcement agencies.

Later in February the row escalated, as Apple announced it was pulling ADP in the UK.

Shortly after that, the BBC learnt Apple was taking legal action by appealing to the Investigatory Powers Tribunal to try to overturn the government's demand.

In a previous statement, a Home Office spokesperson said: "The UK has a longstanding position of protecting our citizens from the very worst crimes, such as child sex abuse and terrorism, at the same time as protecting people's privacy.

"The UK has robust safeguards and independent oversight to protect privacy and privacy is only impacted on an exceptional basis, in relation to the most serious crimes and only when it is necessary and proportionate to do so."