Microsoft has said it is seeing “early signs of stabilisation” but services are not back up and running.

It said system health remains “variable” as traffic is “carefully reintroduced.”

A full report will be shared once the incident is resolved.

Concerns have been raised about Microsoft’s efficiency in finding a solution for the outage.

The tech giant has been scrambling since 6pm last night to resolve the issue, but more than 12 hours later, millions of users are still being impacted.

Prof Awais Rashid, Professor of Cyber Security, University of Bristol, said: “Organisations increasingly rely on third party services such as Office 365. And these services play a critical role in day to day functioning of organisations.

“Whether a cyber security incident or not, their resilience is important to ensure businesses large and small can continue their daily operations.

“What is concerning is not only that an overload issue occurred but, more critically, that Microsoft does not seem to fully understand the underlying cause and apply an effective fix. Cloud systems are large and complex.

“However, capability to ensure their effective operation and mitigation of issues such as this is critical.”

The London Fire Brigade is also affected by the Microsoft outage.

Similarly to the Metropolitan Police, the Brigade confirmed that while some services are facing disruption, its operational response and mobilisation is not impacted and is running as normal.

LFB Assistant Commissioner Jamie Jenkins said: "Like everyone we are experiecing the impacts of the global outage.

"But our operational response and mobilisation is not impacted and running as normal."

The Government Insolvency Service has confirmed it is impacted by today’s outage.

"We are currently experiencing problems sending and receiving emails due to the worldwide Microsoft outage. Our Adjudicator Office service is also impacted," it said.

"Our phone lines are working and if you have any urgent queries please ring 0300 678 0015."

Hospitals, the police, schools, and councils have all been hit by the Microsoft outage this morning.

Parliament is now the next to join the list, reports the BBC.

MPs are struggling to access parliamentary accounts amid the outage.

A parliamentary spokesperson said: “We are aware of the global issue affecting Microsoft email services, which is impacting users of the parliamentary network. We are working with Microsoft to resolve the matter as quickly as possible.

"Alternative communication arrangements are in place, allowing today’s business to continue.”

The NHS is facing major issues accessing Microsoft services on Friday morning.

The Central and North West London NHS Foundation Trust issued a warning to patients, writing: “Patients: please call your usual CNWL service rather than emailing until further notice. Emails may not be received.

“We apologise for any inconvenience.”

London councils are also facing disruption as a result of the Microsoft outage.

Hounslow Council in west London said in a service update that its services had been impacted, explaining that “some of our services may be disrupted today and staff may take longer to respond back to residents.”

Southwark Council also confirmed it was affected by the outage and would be “monitoring” the situation. Emails to and from the council are expected to be impacted.

Experts have weighed in on possible reasons for the Microsoft outage, impacting millions of customers around the world.

Tom Worthington, Honorary Senior Lecturer in the School of Computing at the Australian National University, said: “Rather than a cyber attack, most likely this was caused by an update to software which contained a bug.”

Another expert, Dr Mark A Gregory, Associate Professor in the School of Engineering at RMIT University suggested the outage was caused by a “misconfiguration of networking systems and infrastructure.”

The Met Police has confirmed it is one of the forces facing disruption due to the global Microsoft outage.

The force has advised that some online form submissions may be affected.

It said: “If your report is time-critical but not an emergency, please call 101.

“In an emergency, call 999.”

Several police forces in the UK have urged people not to report crimes online due to problems with Microsoft.

Those forces include Hertfordshire Police, South Wales Police, and Merseyside Police.

Merseyside Police said on its social media that it was “experiencing difficulties receiving online reports” and advised people to use social media channels, the online Bobbi chat, or to dial 101.

It is unclear whether the Metropolitan Police has been affected. The Standard has reached out to the force for comment.