Former communications minister Senator Stephen Conroy has accused NBN Co's corporate affairs head of political bias in tweets she published over a controversial fibre-to-the-premises (FTTP) construction trial.

The construction trial at Melton in Victoria has become a stalking horse for the former Labor government in defending its fibre dominated national broadband network plan.

"Why did you mislead the public?": Senator Stephen Conroy Credit:Alex Ellinghausen

Documents leaked to Fairfax Media about its experimental rollout methods appeared to demonstrate that NBN Co could have rolled fibre connections all the way to premises at a much faster and lower cost if it adopted them before switching to a multi-technology mix (MTM).

When reports of the document first appeared on Fairfax sites, NBN Co's corporate affairs chief Karina Keisler tweeted: "It's an inaccurate report. Note the absence of NBN commentary. No such pilot. MTM NBN is cheaper and sooner".