A FEASIBILITY study is to be recommended into an undersea tunnel between Scotland and Northern Ireland.

The Union Connectivity Review, conducted by Network Rail Chairman Sir Peter Hendy, will be published this week and is reported to recommend a study into the viability of a tunnel connecting Great Britain and Northern Ireland.

The tunnel has been described as a “vanity project” by critics of Boris Johnson, who initially suggested a bridge linking the two countries.

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However the review is said to recommend that civil servants formally appraise the plans for a “fixed link” between the islands, likely between Stranraer and Larne, according to the Sunday Telegraph.

Sir Peter is understood to have rejected a bridge between Great Britain and Northern Ireland on the grounds that it may have to be closed for a third of the year due to bad weather.

Last week Scottish Government transport secretary Michael Matheson blasted the plans, saying they could cost more than £33bn and could take funding away from other more important areas such as schools.

The Scottish Government has refused to engage with Sir Hendy’s review, arguing that transport is a devolved matter.

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Mr Matheson said the project, if it did happen, would not be done in Boris Johnson’s lifetime in an interview with the Daily Record, and added: “Even if something is feasible, it doesn't mean you should do it.

"I suspect the complexities and the challenges associated with some form of fixed link are such that it probably won't happen in my lifetime. And I suspect it won't happen in Boris Johnson's lifetime.

"This is nothing more than a vanity project from Boris Johnson. It's a way for him to try and hide from the fact he's got various problems in Northern Ireland as a result of Brexit, which is causing significant disruption on cross-border trade between mainland UK and Northern Ireland.

"The idea of a fixed link does not resolve those issues. They'll still be there as a result of the Brexit deal agreed with the EU."