Known as SEA-ME-WE 3, the 38,000 km cable links Australia, Asia and Europe. Telstra says the accident affected Indonesia, Japan, Hong Kong, the UK and United States and possibly other countries as well.
The cause of the damage is yet to be determined but a Telstra spokesperson said it could possibly be due to a tension break where excess tension in the cable "pulled it apart".
The race is now on to repair the damage. A ship is due to leave Singapore today and repairs are expected "to be complete within a week from the [original] break", the spokesperson said.
The cable, which is owned by a consortium of around 90 companies worldwide, including Telstra, holds around 60 percent of the ISP’s international Web traffic.
Telstra reported a "normal night" of network operation, with a slightly higher than normal load but fewer people calling the help desk.
The ISP has posted information on its Web site, informing customers that they "will encounter very slow internet traffic due to international congestion issues."
"A cable cut near Singapore [has lead to the] loss of 62 percent of international capacity."