Tasmania’s minority Liberal government will have to find a new deputy premier and treasurer after the state’s second-in-charge resigned amid a Bass Strait ferry “fiasco”.

Michael Ferguson quit cabinet on Monday afternoon after being confronted with the prospect of losing a no-confidence vote in parliament on Tuesday.

He had been under increasing political pressure over delays and cost blowouts to the delivery of new $900 million Spirit of Tasmania ships.

Upgraded berths for the two vessels won’t be ready for their arrival in what the state Labor opposition has dubbed the biggest infrastructure stuff-up in Tasmania’s history.

Labor planned to move a no-confidence motion in Ferguson, with the support of crossbench independents and the Greens, which the Liberals didn’t have the numbers to defeat.

The Liberals govern with just 14 of 35 lower house seats after being re-elected in March.

They were plunged into minority in May 2023 and went to the polls early in the hope of majority but were returned with a larger crossbench.

Ferguson, who has served at state level for 14 years and was touted as a future premier, will remain in parliament.

He said his resignation from cabinet was in the best interests of the government and Tasmania.

“I want to thank the Premier for his support and backing over the past few months – both personally and as a colleague,” he said.

“This friendship is one that I have returned to him during my time as his deputy premier.”

Premier Jeremy Rockliff said Ferguson’s decision was honourable.

“[He] has a number of times … apologised for the situation that we find ourselves in when it comes to the Spirit of Tasmania and the berthing infrastructure,” he said.

Ferguson, who was deputy for two years, in August dropped the infrastructure portfolio over the ferry saga, which he oversaw as minister.

He was accused of misleading parliament, something he denied, about when he knew about cost increases and project issues.

“If a fiasco of this magnitude had occurred in any private sector business, the person responsible would have been sacked a long time ago,” Labor leader Dean Winter said before Ferguson’s resignation.

“The new Spirits project is five years delayed … and when the ships eventually arrive, they will have nowhere to berth.”

Former senators and political veterans Eric Abetz and Guy Barnett, as well as 10-year Bass MP Roger Jaensch, are likely to be in the mix for the deputy role.

-AAP