BORIS Johnson has asked officials to investigate the cost of building a bridge between Scotland and Northern Ireland.

Channel 4 reported tonight that it has obtained documents revealing that the Prime Minister has requested guidance from the Treasury and Department for Transport on the possible costs and risks of such a project.

The PM reportedly asked civil servants to find out “where this money could come from” and “the risks around the project”.

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One of the risk factors is said to include “WW2 munitions in the Irish Sea”.

It comes as the PM held an hour of talks today with Democratic Unionist Party (DUP) leader Arlene Foster and her deputy Nigel Dodds in Downing Street.

Mr Johnson first floated the bridge idea last year, when he was Foreign Secretary.

The Department for Transport produced a “factual paper on the subject” after conversations between the DUP and former Secretary of State for Transport Chris Grayling.

Government spokesman told Channel 4 News: “Government regularly commissions work to examine the feasibility of projects.

"During the leadership campaign candidates spoke about a number of issues which resulted in Number 10 commissions ahead of a new Prime Minister taking over.

"This PM has made no secret of his support for infrastructure projects that increase connectivity for people and particularly those that strengthen the Union.”

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A road connection between the two regions has been championed by the DUP, who said it would encourage economic growth and recognise "the strong economic, cultural and social links between the two regions".

In was first put forward in the party's 2015 election manifesto, but has grown in potential significance since the 2016 Brexit vote. 

Speaking in August 2018, Jane Morrice - formerly the deputy Speaker in the Stormont Assembly and a former head of the European Commission in Belfast - said the link "might help to rid these islands of the dire consequences of Brexit and break the Brussels logjam". 

She added: "A bridge between Northern Ireland and Scotland would literally override any 'border' in the Irish Sea.

"The political and symbolic importance of such a link can't be underestimated."

Scotland's First Minister Nicola Sturgeon has not ruled out the concept, but previously said it had "a lot of challenges" during a visit to Dublin in May. 

Speaking at a hustings event in Northern Ireland in July, while running for leading of the Conservative party, Mr Johnson said he was "an enthusiast for the idea". 

He added: "With infrastructure projects, finance is not the issue, the issue is political will."

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In 2018, architect Prof Alan Dunlop proposed two possible options for the bridge which could connect either Larne and Portpatrick or Mull of Kintyre with Torr Head.

He estimated the cost would be between £15 billion and £20bn.