Responding to a question from opposition shadow communications spokesman Michelle Rowland in parliament on Tuesday, Turnbull said the NBN was a complete catastrophe and a failed project under the Labor Party before the Coalition had changed its direction.
Rowland's question revolved around recent changes to the NBN; the NBN Co stated that the Optus HFC network would not be used for the rollout as planned earlier, and the premises it had been intended to cover would now be served by fibre-to-the-distribution-point (FttDP) connections instead. She said this would increase the cost of these connections.
Turnbull did not answer the question directly, but said that under Labor, construction of the NBN had stopped in many parts of Australia and in other parts it had barely started.
"What is the object? Getting people connected to the Internet with very fast broadband. That is the goal. How do you do it? You do it in the most cost-effective way using the resources you
have, where they are, and you design a technique that suits circumstances. That is what we are doing."
He said the Coalition could have stuck with Labor's "ideological plan, which would have cost another $30 billion and taken six to eight years longer".
NBN Co was connecting new customers at the rate of about 90,000 every four weeks, Turnbull said, adding that 3.2 million premises were now able to access the NBN, while 1.37 million had using the network.
"In six years, Labor connected 50,000. The company is doing as much in two weeks as Labor did in its whole term in government. It is rolling out. Half of Australia's premises will have access by 30 June next year. The company forecasts that it will be three quarters by 30 June 2018, and the project will be completed in 2019-20," he said.
He added that the "turnaround of the NBN is one of the great achievements of the coalition government".