Photo: The NBN board has been under pressure over delays to the NBN rollout. (Reuters)
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All but one of the seven members of the NBN Co board have submitted their resignations to Communications Minister Malcolm Turnbull, the ABC understands.
Chairwoman Siobhan McKenna tendered her resignation along with other board members, but at this stage the Government has not accepted them.
The Government may need to take the resignations to Cabinet for a decision, although it could be dealt with by Mr Turnbull and Finance Minister Matthias Cormann.
But the ABC understands the Government may invite some board members to stay on.
They include Kerry Schott, who has had experience running utilities as the former managing director and CEO of Sydney Water.
Another who could stay is Alison Lansley, a former mergers and acquisitions partner at law firm Mallesons Stephen Jaques.
Mr Turnbull has been highly critical of the NBN board during his time as Opposition communications spokesman, and particularly of NBN Co chief executive, Mike Quigley, who also sits on the board.
Mr Quigley announced his retirement in July after months of pressure over delays to the NBN rollout.
However, he is still in the job to ensure a smooth transition in the early days of the Abbott Government.
Mr Turnbull also criticised Ms McKenna - in particular, pointing out her lack of direct experience in rolling out major telecommunications programs.
He also targeted reported tension between Ms McKenna and Mr Quigley and the way they conducted themselves.
Former Telstra boss likely pick to head NBN Co
Earlier this month, Mr Turnbull said former Telstra boss Ziggy Switkowski would be "highly qualified" and "eminently suitable" to be appointed head of NBN Co.
Before becoming the head of Telstra, the one-time nuclear physicist ran Optus and the Australian operations of Kodak.
Mr Turnbull refused at the time to confirm whether the Coalition would appoint Dr Switkowski as executive director, but the ABC understands an announcement is likely.
Whoever the new chairman is, one of the first tasks will be to oversee a strategic review of the NBN Co, which is slated to start within a fortnight.
The Coalition plans to change the NBN from Labor's fibre-to-the-premise (FTTP) model to a slower but cheaper fibre-to-the-node (FTTN) model.
Telstra has built a test site in a laboratory to test the Government's preferred option and began a trial just after the election.
A spokeswoman says the trial is "going well" but says Telstra has not "demonstrated its capabilities to anyone yet".
A petition, launched earlier this month by Queensland university student Nick Paine, calling for the Coalition to endorse the FTTP model has gathered more than 250,000 signatures.
Mr Turnbull responded, saying the party's election win gave it a mandate to go ahead with its NBN plan.
"The promoters of this petition apparently believe that we should ignore the lengthy public debate on the NBN that preceded the election and also ignore the election result," he said.
"[That] we should, within days of the election, walk away from one of our most well-debated, well-understood and prominent policies.
"Democracy? I don't think so."
Mr Turnbull has been unavailable for comment this morning.
Editor's note: An earlier report said all members of the NBN Co board had offered to resign. The ABC understands only six of the seven board members have tendered their resignations.
