A UK minister's idea to replace ferries with underwater tunnels has received a terse response from transport secretary Jenny Gilruth's office.

During a “fact-finding” visit to the Faroe Islands, Scotland Office minister Iain Stewart  said talks should also begin in the Orkney and Shetland archipelagos, “given the timescales of these sorts of projects”.

It comes after the Scottish Government said it was exploring the construction of fixed links in the Western Isles and between Mull and the mainland.

There are currently four tunnels on the Faroes — including the world’s first underwater roundabout — and a fifth under construction, all replacing former ferry routes and dramatically cutting travel time to remote islands.

The Scotland Office minister met with officials in the Faroes to discuss the huge infrastructure project and suggested similar proposals could be used in Scotland.

The minister conceded the projects would be “not cheap”, saying the Faroes' scheme cost as much as £12.5m per mile.

A spokesman for Scotland’s transport ,inister Jenny Gilruth said: “Given transport is a devolved matter, it’s no wonder Iain Stewart has plenty of time on his hands, jet-setting across to the Faroes during a cost of living crisis.

“Island communities will be intrigued as to what facts the Milton Keynes MP has been gathering.”

The spokesman added: “If Mr Stewart is interested in sharing any of the facts he has gathered from his trip, the Scottish Government would be more than willing to hear them, recognising, as Mr Stewart will of course respect, that transport is devolved.”

The Herald:

The UK minister is expected to have discussions with the SNP Government and officials on the idea’s potential.

The Scottish Government has already plans to create bridges or tunnels between islands including from Scotland's mainland and Mull to "improve communities access to goods and services".

The proposal revealed in January seeks to replace ferries with fixed links 26 years after the opening of the Skye bridge was mired in controversy.

Net zero, energy and transport secretary Michael Matheson said the plan could see another crossing to Mull, which has been hit with ferry disruption. A bridge from Oban to the nearest community on Mull would be around ten miles long.

He also talked of a plan of a fixed link between North and South Uist and Lewis and Harris.

According to Mr Stewart there were limitations in connecting some islands to the Scottish mainland.

But he said: “Given the distances between some of the islands are fairly small, for example, between Unst and Yell in Shetland, it could be a viable option.”

He added: “It’s not going to be cheap but contrast that against building several new ferries, not just once but — given those tunnels would be there for many, many years — probably two or three cycles of building ferries.”

While local objections, costs and logistics migh prove to be obstacles, Mr Stewart said the experience of the Faroes “shows it can be done".

The UK Government spent £900,000 on expert assessment of the so-called Boris bridge, which was either a bridge or tunnel which would connect Scotland to Northern Ireland, before determining it would cost as much as £200bn to realise, and may require feats of engineering not yet developed. It was described by some critics as “the world’s most stupid tunnel”.

One idea involved as many three tunnels heading out from England and Scotland with a roundabout beneath the Isle of Man in a bid to iron out post-Brexit issues across the UK.

The Herald: File photo dated 17/11/2009 of a train leaving the Euro Tunnel at Coquelles in France. Thousands of migrants stormed Eurotunnel's French terminal in Calais last night. PRESS ASSOCIATION Photo. Issue date: Tuesday July 28, 2015. Over the course of the nigh

It took just under six years and 13,000 workers to build the Channel Tunnel, which opened in 1993. The total cost came at an eye-watering £4.65 billion which would be more than £12 billion in today's money, according to Eurostar.

Mr Stewart suggested funding could come from a combination of Scottish Government money and the UK’s Levelling Up fund.  He even suggested tolls.

“If these tunnels are built, you’re looking at many generations of sustainability," he said.

“Environmentally, it’s got a benefit, particularly as everyone electrifies their motor transport.

“Shipping is one of the most polluting forms of transport..

Sigurd Lamhauge, chief executive of Faroes transport authority Landsverk, said: “The tunnels have led to increased incomes, improved access to healthcare and education, better commuting times and more people staying on the islands. They have brought positive change and I would think something similar would have the potential to do the same to places like Orkney and Shetland.”