Former Nationals deputy leader left without pathway back to Senate as Barnaby Joyce campaigns in New England

The high court’s decision to disqualify the former Nationals deputy leader Fiona Nash is likely to spell the end of her political career, with a growing acceptance she will not be reappointed to her vacated seat or contest the next election.

On Friday the high court unanimously held that Nash was ineligible for election because she held British citizenship by descent from her Scottish-born father.

A recount election is likely to return Liberal Hollie Hughes, who held sixth spot on the Coalition’s New South Wales Senate ticket at the 2016 election and wants to retain the seat.

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While there were suggestions that Nash wished to stay in politics, and that Malcolm Turnbull could intervene on Nash’s behalf, hopes have now faded that such an intervention will take place or could succeed at persuading Hughes to relinquish the spot.

Guardian Australia understands that there is now acceptance in the Nash camp that her political career is unlikely to continue and that she is extremely unlikely to make a comeback by seeking re-election.

On Sunday the NSW Nationals senator John “Wacka” Williams ruled out bringing forward his retirement to create a vacancy for Nash, telling Guardian Australia he would stay in parliament until the end of his term on 30 June 2019.

Nash’s exit is expected to spark internal debate between the NSW Liberal and National parties over the Senate ticket before the next election, with suggestions that the replacement of Nash by a Liberal will require an increase in the number of Nationals selected for winnable spots.

On Friday Turnbull thanked Nash for her service to the government and parliament, saying she had been “an outstanding minister, passionately devoted to regional Australia and its advancement”.

After he was also ruled ineligible on Friday, Barnaby Joyce began campaigning for the New England byelection, to be held on 2 December.

At a doorstop in Bendemeer on Sunday, Joyce said in retrospect it would have been better to “get straight into” a byelection rather than wait for the high court’s decision but he had not wanted to incur unnecessary expense if he were eligible, as the government’s legal advice suggested.

Joyce said it was a decision of the cabinet to nominate the deputy Liberal leader, Julie Bishop, as acting prime minister in Turnbull’s absence rather than the interim Nationals leader, Nigel Scullion, who he said would have made a good acting prime minister.

“It was not my decision,” Joyce said. “The deputy prime ministership has been held in abeyance, that’s the big one, and let’s hope the people of New England find it in their hearts to give me a run at it again ... and we can fix that problem up right away.”

Joyce is the favourite in part because the former independent MP Tony Windsor opted against running but it is still unclear who he will face in the byelection.

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The ABC has reported that One Nation is unlikely to field a candidate, Labor and the Greens will run and that so far only independent Rob Taber and the former West Australian Liberal MP Ian Britza have declared their intention to nominate.

The Shooters Fishers and Farmers party will make a decision about whether to run early this week.

The former Greens senator Larissa Waters is pushing for a comeback through the Queensland Senate preselection process, which could see Andrew Bartlett gain her seat in a recount but allow Waters to win it back at the next election or take it back earlier by agreement.

On Sunday the South Australian Greens senator Sarah Hanson-Young told ABC News that Waters had been “upfront about the fact that she doesn’t feel like her work has finished”.

“The Queensland branch of the Greens will be making decisions about preselection for the next election, the 2018/19 election and it will be up to them to decide who they want to represent them,” she said.

Hanson-Young said that Bartlett could “hit the ground running” because he had been in parliament before – he previously represented the Australian Democrats – but said that the preselection provided a “pathway” for Waters.

Hanson-Young accepted that the Greens processes, particularly in Queensland and Western Australia, “need to be cleaned up” to prevent disqualification for foreign citizenship.

But she praised Waters and Scott Ludlam for resigning their positions, compared with the “absolute arrogance” from Joyce and Nash who stayed in parliament pending the high court decision.