A cable cut in Oregon has put the fragility of New Zealand's internet connections back under the spotlight.

New Zealand's internet connection to the United States has survived a cable cut in Oregon on the US west coast.

Southern Cross Cable Network confirmed a segment of its cable network was cut at about 1am New Zealand time when a contractor working for the state's transport department in the town of Klamath Falls cut through it with a digger.

Spokeswoman Rosemay Foot said the cable was repaired in a little under nine hours.

Southern Cross' network is configured as a "figure of eight" centred on Hawaii. The design means there is always one back-up route if a section of the cable is cut.

The land-based "E2" segment of the cable that runs between Oregon and San Jose that was cut has an addition terrestrial back-up. But Foot said its "first choice" was to instead switch circuits across its international links.

Traffic that would usually run between the US and Australia was diverted via New Zealand.

Foot said New Zealand customers of Southern Cross had not been affected by the cable cut and nor had other customers who had paid for capacity via a back-up route.

However, the outage had some impact on customers outside New Zealand who had not paid for "protected circuits", she said.

Southern Cross Cable Network confirmed the incident several hours after it was first approached by Stuff for comment. Foot said it advised customers of the cable cut within 15 minutes "but does not make public releases about operational issues".

"We reiterate there was no loss of service to any protected services and there was no impact to any New Zealand originating or terminating service," she said.

Foot revealed there had been another cut on the same link in February when a boring machine cut through its fibre-optic cable near Sacramento.

Several attempts have been made to build a business case for an additional fibre-optic cable that would link New Zealand to the US and reduce the country's reliance on Southern Cross.

Hawaiki Cable secured a carrier licence in April from Communications Minister Amy Adams for its proposed subsea cable that would run between Sydney, Whangarei and Oregon.

However, it has yet to confirm it has secured the US$300 million ($410m) in funding that it needs to begin construction.

Foot said the significant advantage of Southern Cross was that it was a "dual cable network".