The communications minister has refused to take blame for the slow and expensive roll out of Australia’s national broadband network.

In a grilling interview with TODAY Show co-host Karl Stefanovic, Minister for Communications, Senator Mitch Fifield, backed the current government's roll out of the network.

"We've turned it around, we’ve got in on track," Senator Fifield said.

"NBN is now available to half the nation and it’ll be 75 percent by the middle of next year," he added.

"It will be all done and dusted by 2020.

"That's six to eight years sooner than it would have been the case under our predecessors."

Senator Mitch Fifield was grilled by Stefanovic this morning.

Stefanovic asked Senator Fifield to fast-forward to 2020 and give his 30-second pitch to sell the "great turkey" to investors.

"This is a national broadband network, we’re the first continent this sort of fast-broadband network," Senator Fifield said.

"It's fit for purpose and it’s over to investors."

Stefanovic asked Senator Fifield why he won't take responsibility for the massive bungle.

After an awkward pause, a baffled looking Stefanovic asked: "That's your pitch?"

"You're not going to be able to sell it, who is going to buy it?" Stefanovic asked.

"Australians just want hard talk from their politicians, they want you to take responsibility," he said.

Stefanovic laughed after Senator Fifield gave his pitch for NBN.

"It might not have been your fault and certainly you’ve had a chance to try and fix it, but they just want you to take responsibility."

But Senator Fifield said the government is taking responsibility.

"It has it challenges, but our job isn’t to look into the rear view mirror, our job is to get this thing rolled out."

The Turnbull government yesterday took a swipe at internet retailers and Labor in a bit to deflect consumer anger over NBN .

NBN is expected to be fully rolled out by 2020.

The project has cost Australian taxpayers billions of dollars.

It was also admitted the network is not commercially viable as retailers decline to purchase sufficient bandwidth while aggressively competing against each other for new customers who aren't prepared to pay more for faster broadband services.

The NBN is trialling fibre-to-the-curb technology, which takes cable to telecom pits outside premises, which is closer than fibre-to-the-node as well as cheaper and less complex than fibre-to-the-premises.

NBN Co expects to serve an initial one million premises with FTTC and estimates the technology will cost about $2900 per premises to deliver compared to $4400 for FTTP.