Government officials have begun examining whether a bridge connecting Scotland and Northern Ireland is viable, Downing Street has confirmed.

As part of Boris Johnson's "ambitious" vision for major infrastructure projects, a "range of officials" are now looking at the possibilities for building a bridge spanning the Irish Sea.

This morning the Prime Minister's spokesman said a "proper piece of work" was underway, after Mr Johnson repeatedly raised the idea in recent months.

However, he is likely to face fierce resistance from opposition MPs over the plans, with experts warning that the depth of the Irish Sea and the presence of dumped munitions would cause problems for any project.

The price tag for the project is also expected to be £20bn, although Mr Johnson has previously provided an estimated of £15bn.

Taking questions from reporters this morning, his spokesman said: "The PM set out this was an idea which he believed could have some merit so, as a result of that, you would expect the Government to be looking into it."

"The PM is ambitious in terms of infrastructure projects. He's looking at a wide range of schemes across the UK which could improve connectivity."