Google for Work's business users worldwide are experiencing a service disruption that is hindering their use of the Gmail email, calendering and contacts application.
The outage started at 1.16 am Australian eastern standard time. Google said the outage only affected its business-focused Gmail for Work customers.
According to the company's Google Apps service status page, the outage is ongoing.
Service has been restored for some users, but Google did not provide an estimated time of full resolution. The company's Google for Work Twitter account said a fix was in the works, but did not specify what the problem was.
The company warned that delivery of messages sent to affected users during the outage may be delayed.
Affected users are advised to contact Google Apps support in the United States via phone, email or chat. Email and chat support require customers to be signed in with their super administrator accounts.
Google did not immediately respond to enquiries about the outage.