CAPITAL cost forecasts for the National Broadband Network have blown out by 3.9% - or about $4.6 billion - but the government says it remains below the $43 billion originally announced.
The latest corporate plan for the huge infrastructure project, for the period 2012-15, was revealed on Wednesday by Communication Minister Stephen Conroy and NBN Co chief Mike Quigley.
It was the only cost update the public has been offered since original estimates were produced in 2010.
While the costs have risen, the revenue the government expects to pull from the project also rose, 0.1%, bringing total revenue to 7.1%.
The new plan also projected some 758,000 premises would be passed by fibre optic cable by the end of the year, with about 305,000 passed so far this year.
But the plan also provided no new detail on which areas outside of capital cities would be given priority.
Construction time for the complete project was also delayed by six months to June 2021, partly on the back of delays to a deal with Telstra.
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