One of the brand new Spirit of Tasmania ships will be temporarily relocated to a shipyard in Scotland for an unknown amount of time as ferry operator TT-Line explores options to lease out the vessel.

The first of the larger Bass Strait ferries was due to arrive in Tasmania at the end of this year, but the berth in Devonport will not be ready until February 2027.

The ships are being built in Rauma, Finland. However, the ship's operator said in a statement Spirit of Tasmania IV would need to leave the country before icy conditions set in at the end of November.

Spirit of Tasmania chief executive Bernard Dwyer said the "ice pack conditions posed potential operational risks" for Spirit of Tasmania IV.

"To ensure the vessel's safety and preservation, we will temporarily relocate it to Leith, Scotland, where conditions are more suitable," he said.

It is unknown how long Spirit of Tasmania IV will stay in Scotland.

The ships will undergo a final fit out in Tasmania.

Mr Dwyer said TT-Line was continuing to explore options to lease or charter the vessel.

He said construction of Spirit V would continue as planned and would be not be affected by the icy conditions because it was yet to undertake a sea trial and its engine had not been commissioned.

The new ships have been described as a "game changer" for Tasmania's tourism industry, with them boasting 40 per cent more freight- and passenger-carrying capacity.

But construction delays and cost blowouts, as well as the delayed construction of a deeper berth the new ships require, has resulted in the Tasmanian government being heavily criticised over its handling of the rollout, with the minister overseeing the infrastructure portfolio resigning.

It was revealed days ago that the berth — that was supposed to be built by August 2024 — would not be completed until October 2026 at best. It is more likely to be finished in February 2027.

This means Tasmania will not have its new ships in full service for years they would not be able to use the existing, shallower berth unless they operated at lesser capacity.

The Tasmanian government has said it is open to leasing the ships out to recoup expenses, with that not being TT-Line's preferred option.

The saga has embroiled the ferry operator as well as the state-owned port operator, Tasports, which have all fronted a parliamentary committee tasked with finding out what has gone wrong.

It has been estimated that for every year the rollout of the new vessels is delayed, the Tasmanian economy loses $350 million in revenue.