Shadow communications minister Malcolm Turnbull has renewed his call for NBN Co to release a revised business plan for the NBN, after Telstra raised doubts about NBN Co’s pricing strategy and financial modelling.

Telstra’s move to question NBN Co’s economics is the first significant public clash between the telco and the company since they signed the dotted line on the $11 billion deal and Mr Turnbull has seized the opportunity to turn the screws on the government.

The opposition frontbencher has told The Australian Financial Review that given NBN Co’s status as a wholesale monopoly it must be subject to rigorous scrutiny.

“Given its market power and monopoly status, the onus should be on NBN Co to be transparent, fair and consistent in its dealings with carriers,” he said.

He added that NBN Co should do what it takes to get Telstra to sign its wholesale broadband agreement, which most other telecommunications companies have signed, before the Australian Competition and Consumer Commission (ACCC) is asked to approve NBN Co's special access undertaking (SAU).