The Federal Government has questioned the viability of a high speed rail line through Canberra, arguing building the link would be disruptive, noisy and expensive.

NSW Premier Barry O'Farrell wants Canberra Airport to act as a second airport for Sydney, with a high speed rail line linking the two cities. Canberra airport is enthusiastically backing the plan.

But speaking at the Sydney Institute on Monday night, Infrastructure Minister Anthony Albanese

said the study he commissioned into the project would require a 1750km track, and 144km of tunnelling, most of it in Sydney.

Mr Albanese said he was not arguing against a Brisbane to Melbourne link, which is planned to go through Canberra, but predicted that high speed rail's greatest advocates might struggle with the realities of building the major piece of infrastructure.

"I predict that when I release the high speed rail study in coming months, some of the strongest opposition to the reality that such an ambitious proposal represents, will be from those who embrace the abstract idea of high speed rail," he said.

"But as a concept, not as the reality that has a wide corridor, major tunnelling, significant noise impacts, and that's before we consider the significant economic costs."

Mr Albanese said as a train passed on the high speed rail, the noise would reach 100 decibels.