Bob Geldof has been steadfast in his opposition of the Brexit vote since it was passed in June of 2016, and has now joined forces with a host of other musicians to write a letter to the UK's Prime Minister Theresa May. Describing the referendum and subsequent result as "madness", the letter penned by the former Boomtown Rats front man delineates the potentially huge adverse effect leaving the EU could have on the music industry.

The letter was also signed by the likes of  Ed Sheeran, Sting, Damon Albarn, Jarvis Cocker, Rita Ora, and Johnny Marr among others, and it implores May to rethink her plans for when the UK departs from the EU next March.

In it, Geldof states that the music industry is largely dominated by British artists, writers, producers, engineers and others, and that the effects of Brexit could cause them to be imprisoned in a "self-built cultural jail". The singer-turned-activist claims that as a consequence everything from artists' touring, merchandise and record sales, copyright laws and royalties could be harmed if the case is that they are to be denied the EU's freedom of movement rules that leaving the union would entail.

Many commentators believe that a second referendum is necessary in the UK, a sentiment Geldof shares because of reasons alluded to in the letter and more.

Originally published in The Observer newspaper, the letter can be read in full below.

"To Theresa May:

Imagine Britain without its music. If it’s hard for us, then it’s impossible for the rest of the world. In this one area, if nowhere else, Britain does still rule the waves. The airwaves. The cyberwaves. The soundwaves. It is of us. It is our culture.

We dominate the market and our bands, singers, musicians, writers, producers and engineers work all over Europe and the world. In turn, Europe and the world come to us. Why? Because we are brilliant at it. No one quite knows why this should be but everyone understands it to be so. The sound and the words seem universal. It reaches out, all inclusive, and embraces anyone and everyone. And that truly is what Britain IS! That is proper Global Britain.

But Brexit threatens, as it does so much else, this vast voice. This huge global cultural influencer. We are about to make a very serious mistake regarding our giant industry and the vast pool of yet undiscovered genius that lives on this little island.

Why are we closing down these possibilities for ourselves and for those as yet unknown to us? Brexit will impact every aspect of the music industry. From touring, sales, copyright legislation, to royalty collation. Indeed it already has. As a result of the referendum vote, the fall in the pound has meant hugely increased equipment costs, studio hire, and touring costs all now materially higher than before – and not forgetting that squeezed household incomes means less money to go to clubs and buy tracks, T-shirts, gigs and generate the vast income necessary to keep the up and comers on the road and musically viable.

A massive 60 per cent of all royalty revenue paid to the UK comes from within the EU. And at home, any increase in import duty will mean that anything that comes to us from outside will cost significantly more. We have decided to put ourselves inside a self-built cultural jail! The very opposite of wall-destroying, prejudice-denying, ideas-generating that is the very essence of contemporary music. And yet it is the much-mocked freedom of movement that so effortlessly allows our troubadours, our cultural warriors, to wander Europe and speak of us to a world that cannot get enough of [them], and which generates countless billions for our threatened institutions.

This is all a serious madness. We must take back our future.We must reform and restructure the EU. When Europe is in a mess, the Brits get stuck in. They don’t withdraw, they double down. They get in close and messy. Make Europe the continent that we and the people of Europe want. Not the one dreamt up in another time by the ideologues, or by the undemocratic fiat of mediocre politicians or the dull exhortations of a pallid bureaucracy. A new one. A different one. An exciting one. A rock’n’roll one.

Let’s rock Europe and let’s save our music, our musicians, our music jobs and our songs. Let’s save our voice.

Yours, Bob Geldof and friends."