Tasmania's Liberal leader has lobbied the Federal Communications Minister over revised plans for Tasmania to receive slower broadband over the copper network.

The head of NBN Co, Ziggy Switkowski, has revealed the old copper network will be used as part of Tasmania's rollout, saying contracts do not specify the faster fibre connection to the home as anticipated.

About 70,000 premises are expected to have fibre connection by the end of the year, but after that the fibre rollout will start to wind down.

Liberal Leader Will Hodgman says he picked up the phone to Communications Minister Malcolm Turnbull as soon as he heard about the plan.

Mr Hodgman says it is critical infrastructure and he wants to see the best possible service delivered, but that it has to be efficient and affordable for the Federal Government

"It's a federal project but I'll argue strongly our preferred position is fibre to the home. I don't resile from that, and that's what I'll argue for," he said.

Premier Lara Gidding has accused the Coalition of misleading voters.

"They were careful before the election to give the impression they supported the NBN, they supported the rollout of the contracts that were here in Tasmania to deliver fibre to the door of Tasmanians," she said.

Tasmanian Greens leader Nick McKim has criticised the revised rollout plan, saying using copper is a short-term fix.

"Ziggy Switkowski should know that it is impossible to say what uses people will want to engage the internet for in 10, 20 or 50 years' time."

The industry lobby group Tas ICT has urged Mr Turnbull to come to Tasmania to explain the repercussions.

Spokesman Dean Winter says it is disappointing Tasmania will not get a full fibre rollout.

"It is going to be inequitable. There's going to be a lot of towns and suburbs that potentially won't get the fibre-to-the-premises they were originally promised and that's very disappointing for those areas," he said.

"Really there's going to be a fight amongst those towns and between local mayors and municipalities about who is going to get that superior NBN."

Two-tiers of technology

33,000 homes and businesses already have NBN access, another 36,000 are expected to be connected by the end of the year, leaving about 150,000 properties in limbo, the equivalent of the half the state.

People living in the same street may find they have different technology under the changes, with some homes connected to superfast fibre while their neighbours have to put up with upgraded copper connections.

The Clarence Mayor, Doug Chipman, calls that situation unfair.

"If some businesses have the NBN and other don't then those businesses will have the competitive edge, those schools that are connected," he said.

John Dalton of Digital Tasmania believes property values will be affected.

"Dr Switkowski has said if you don't get fibre by the end of the year you don't get it, so chances are if you're not in build right now you're out of luck," he said.

Stakeholders and mayors who met the NBN Co chief say he could not clarity which areas will be left off the map.