The social media boss said he was ‘sorry for the disruption’ after it emerged he had personally lost more than £4.4billion due to Facebook stock plummeting.

Shares in the company fell by 4.9 per cent on Monday as the firm struggled to deal with both the global outage and bombshell claims made by a whistleblower.

Frances Haugen, a former product manager at Facebook, said the business “chooses profits over safety”.

Mr Zuckerberg has now reacted to the crisis and apologised for the chaos caused by Monday’s crash.

Facebook stock has plummeted due to the crash, causing Mr Zuckerberg to lose billions

He said: “Facebook, Instagram, WhatsApp and Messenger are coming back online now. Sorry for the disruption today — I know how much you rely on our services to stay connected with the people you care about.”

The issues were caused by a faulty configuration change, according to Facebook.

Explaining the outage, Facebook said: “Our engineering teams have learned that configuration changes on the backbone routers that coordinate network traffic between our data centres caused issues that interrupted this communication.

“This disruption to network traffic had a cascading effect on the way our data centres communicate, bringing our services to a halt.”

The company said it had been “working as hard as we can” to restore access and that the underlying cause had “impacted many of the internal tools and systems we use in our day-to-day operations”.

Users were able to access Facebook and Instagram from late on Monday evening, while WhatsApp said just after midnight its services were “slowly and carefully” being restored.

At 3.30am, WhatsApp confirmed its services were “back and running at 100 per cent”.

In a statement, WhatsApp said: “We’re aware that some people are experiencing issues with WhatsApp at the moment.

“We’re working to get things back to normal and will send an update here as soon as possible. Thanks for your patience.”

Instagram released its own statement that said: “Instagram and friends are having a little bit of a hard time right now, and you may be having issues using them. Bear with us, we’re on it.”

The platforms had confirmed on Twitter they were aware of issues and worked to resolve them after thousands of people reported outages shortly before 5pm on Monday.

More than 75,000 complaints were received about WhatsApp and more than 30,000 Instagram users also had similar complaints.

Facebook’s share price plummeted 4.9 per cent during the outage, reducing the company’s total value from $967billion (£710billion) on Friday afternoon to $916billion (£670billion) by Monday’s closing bell.

It comes after former Facebook product manager Frances Haugen, provided The Wall Street Journal with internal documents and is scheduled to testify before a US Senate subcommittee on Tuesday

For hours, Facebook’s only public comment following Monday’s outage was a tweet in which it acknowledged that “some people are having trouble accessing (the) Facebook app” and said it was working on restoring access.

Mike Schroepfer, Facebook’s outgoing chief technology officer, later tweeted “sincere apologies.”

Although much of the company’s workforce is working remotely, there were reports that employees at the company’s Menlo Park, California, campus had trouble entering buildings because the outage had rendered their security badges useless.