Updated 8.30pm

GO's internet and mobile data services are returning slowly after thousands of customers were unable to get online on Thursday afternoon.

The telecommunications company experienced a fault at around 4.15pm. By around 8pm, the service was slowly being restored and reports were being received that the internet service was returning.

In a statement, the company said services were being restored.

"We suffered a major outage on our international connectivity which impacted all internet services, as well as certain dedicated business services. Our engineers, and foreign counterparts, have worked tirelessly to diagnose and restore services as soon as possible."

GO said the timing of the outage was unfortunate because it coincided with its earlier announcement that the company was closing its retail outlets early due to the annual staff party. 

"Our clients’ interests always come first and consequently the party was cancelled. GO also took the decision that all the catering that was ordered for the party has now been donated to those in need.

"Our teams are still working hard to ensure that all services are back to normal.  The incident is deeply regretted," the company said.