"The cost of the NBN is rising as we speak."
That's according to NBN Co Chairman Ziggy Switkowski, who was grilled today at a hearing of the Senate Select Committee on NBN.
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The confronting questioning from Senators Stephen Conroy and Scott Ludlam comes just days before NBN Co hands its Strategic Review to Communications Minister Malcolm Turnbull.
At the hearing, Conroy accused NBN Co of misleading parliament as to the cost per household of the NBN rollout, and took Switkowski to task over the cost and timing of the rollout, the viability of using the existing copper network, and the lack of public information with regards to construction of the network.
Conroy told the hearing he was "staggered" that Switkowski would contradict the numbers previously presented to the committee on the cost per household of the NBN.
"Has the parliament been systematically misled?" Conroy said.
"If you give them (contractors) more money for failing to do their job properly, it is on your head. "If you choose to reward incompetence, that's on your head."
Conroy was referring to ongoing negotiations with contractors building the NBN.
While Switkowski would not reveal the exact increase in costs, he denied he was misleading the parliament. "You were not misled," he said. "My own recent experience, when you go out into the field confirms that the costs are higher than what people have hoped they would be.
"As we continue to look at actual costs you have a better feeling, and the costs look higher, and I would say substantially higher.
Switkowski said the "cost issue" was one of the key elements of the review.
"That number (connection cost per household) is rising as we speak," he said. "Costs are connected to our prices and connected to experiences that were not expected."
Switkowski also defended the use of the copper network and said he had changed his mind about copper.
"Copper has since turned out to be more robust than anybody thought," he said.
When confronted with pictures of NBN construction taking place in Mudgee, Dubbo and Western Australia, while there was no information on the Website, Switkowski said information would be added when it reached the appropriate build phase.
"The fact that large sections of the country have been removed does not mean they are not getting NBN, it does not," he said.
"The mere changing does not reflect any change in the priority or strategy in the build," he said.
Conroy also asked if NBN Co would meet its deadline to bring 25 Mbps to all homes by 2016 following a leaked internal NBN Co document indicating it would not be achieved.
Switkowski said the target would be "very challenging".