Following a world outage Google services are now back online - YouTube and Google's other services like Gmail, Maps, Drive and Photos have all been fully restored, Reuters and Bloomberg reported Tuesday.

The nearly hourlong glitch Monday prevented users worldwide from getting on these apps. "We'll continue to work toward restoring service for the remaining affected users," Google wrote in a post on its service status page. The company did not provide details on what caused the outage.

Google said the outage was not the result of a cyberattack but an internal issue with one of its authentication systems.

DownDetector, a website specializing in portal outages, said the temporary shutdown had a tremendous effect on every service of the search company - including its smart home service Nest.

According to DownDetector, more than 12,000 YouTube users lost connection in different parts of the world - mainly in countries like the UK, Germany, Portugal, France, Greece, Russia and Poland.

Around 90% of affected users said it failed to log in to Google while 9% reported browser search was down, the monitoring site reported.

Interruptions were monitored in the Asia-Pacific - affecting countries such as Japan, Indonesia, India and Australia. In America, services were down in the U.S. and many Latin American countries, like Mexico, Colombia, Argentina, Brazil and Peru.

Alphabet Inc.'s Google has some of the most heavily used services in the world: more than 2 billion people use YouTube each month, with visitors viewing more than a billion hours of video on the site.

As of October last year, around 1.5 billion people had an active Gmail account, CNBC reported. Google's email service is the world's largest. Its closest competitor, Microsoft Outlook, hosted about 400 million active users as of 2019.