Australia's National Broadband network has come into doubt again, after the company set up to manage it ÔÇô the National Broadband Network Company ÔÇô suspended its cabling tender process, saying prices were too high.

The move has made opponents question the forward planning of the group, with concerns prices could further rise due to future wage increases and skills shortages if it is delayed too long.

NBN Co head of corporate services Keven Brown said disagreements had formed on the assumption of 14 construction businesses involved in the process for the last five months regarding pricing regimes. 

Brown said the group had benchmarked against similar civil works and engineering projects in Australia before making its decision, and said it would instead look to other ways of carrying out the tender and construction process.

The National Broadband Network has been labelled Australia's most expensive, with an estimated cost of US$36bn, and its most ambitious infrastructure project yet. It aims to provide high-speed broadband services to most of the population.

The fiber portion alone for the project is estimated to cost more than US$12bn.

Brown told ABC radio prices were out by double digits on what had been expected.

There are rumours that NBN Co is now talking with Leighton Holdings regarding the project.