An update to the NHS Covid-19 app has been delayed after it was blocked by Apple and Google on privacy grounds.

As coronavirus lockdown measures were eased across the UK from midnight, the NHS Covid-19 app was meant to include a new feature that would have allowed users - once they had tested positive- to upload the list of all venues they had checked in to using a QR code.

But this form of location tracking has been explicitly prohibited on privacy grounds by Apple and Google, who collaborated together to design the exposure notification system used on all iOS and Android devices.

Public health authorities around the world that signed up to the exposure notification system have agreed to never use it to collect location data, but this was what Apple and Google considered would have happened under the update to the app.

Although the app is called the NHS Covid-19 App, it is actually run by the Department for Health and Social Care and not NHS England.

A spokesperson for the Department for Health and Social Care said: "The deployment of the [enhanced check-in] functionality of the NHS Covid-19 app to enable users to upload their venue history has been delayed.

"This does not impact the functionality of the app and we remain in discussions with our partners to provide beneficial updates to the app which protect the public," they added.

The statement continued: "As venues begin to open up we encourage everyone who can to use the enhanced venue check-in process, which includes advising users to book a test if they attend venues where multiple people have tested positive."

Neither Apple nor Google immediately responded to a request for comment.

It comes as England made its next step on the roadmap out of lockdown.

April snow showers made outdoor service at pubs and restaurants a chilly prospect in parts of southern England, but the wintry conditions appeared to do little to dampen enthusiasm for mixing outside.

Some pubs and hairdressers opened at midnight, while shoppers were queuing outside shops early this morning as high street retail opened up.

The prime minister urged caution during the "major step forward" as a scientist advising the government warned the rules must be followed to minimize a possible rebound in infections.

The next step in easing lockdown, as per the prime minister's plans, is the 17 May, when socializing indoors will be permitted under the "rule of six".