Miley Cyrus
Miley Cyrus arrives for a performance on the Village stage during the iHeartRadio Music Festival in Las VegasReuters

The feud between Miley Cyrus and Sinead O'Connor is getting dirtier by the day with the singers taking a dig at each other in public, and now, "Nothing Compares 2 U" hitmaker has threatened to sue "Wrecking Ball" singer for mocking her and Amanda Bynes for their 'illness'.

Sinead O'Connor wrote an open letter to Miley Cyrus, which she said was done in "spirit of motherliness and with love", not to be "prostituted by the music industry". She responded after the Hannah Montana star said in an interview to Rolling Stone magazine that the music video of "Wrecking Ball", in which she appears completely nude, was inspired by her "Nothing Compares 2 U" video.

"I am extremely concerned for you that those around you have led you to believe, or encouraged you in your own belief, that it is in any way 'cool' to be naked and licking sledgehammers in your videos. It is in fact the case that you will obscure your talent by allowing yourself to be pimped, whether its the music business or yourself doing the pimping," wrote the 46-year-old singer on her official website.

"The music business doesn't give a shit about you, or any of us. They will prostitute you for all you are worth, and cleverly make you think its what YOU wanted.. and when you end up in rehab as a result of being prostituted, 'they' will be sunning themselves on their yachts in Antigua, which they bought by selling your body and you will find yourself very alone."

O'Connor went on to say that she should send out healthier messages to her peers and asked her to apologise to former child actress Amanda Bynes, who suffers from bipolar disorder, for mocking at her illness.

However, O'Connor's letter seemed to have not gone down well with Miley, as she took to twitter to hit back at her. Miley not only mocked her illness but also posted a  photo of O'Connor tearing up a photo of Pope, which was done in protest against alleged child molestation prevailing in the church.

O'Connor has written three open letters to Miley Cyrus so far after she continued to take a dig at her on twitter. The first letter was in response to "Wrecking Ball" singer's interview to Rolling Stone; second letter was after she mocked her and Amanda Bynes of their illness; and the third one was after she tweeted: "Sinead. I don't have time to write you an open letter cause Im hosting & performing on SNL this week. So if youd like to meet up and talk lemme know in your next letter. :)"

Here is complete text of Sinead O'Connor's First Letter to Miley Cyrus:

OPEN LETTER TO MILEY CYRUS

Dear Miley,

I wasn't going to write this letter, but today i've been dodging phone calls from various newspapers who wished me to remark upon your having said in Rolling Stone your Wrecking Ball video was designed to be similar to the one for Nothing Compares... So this is what I need to say... And it is said in the spirit of motherliness and with love.

I am extremely concerned for you that those around you have led you to believe, or encouraged you in your own belief, that it is in any way 'cool' to be naked and licking sledgehammers in your videos. It is in fact the case that you will obscure your talent by allowing yourself to be pimped, whether its the music business or yourself doing the pimping.

Nothing but harm will come in the long run, from allowing yourself to be exploited, and it is absolutely NOT in ANY way an empowerment of yourself or any other young women, for you to send across the message that you are to be valued (even by you) more for your sexual appeal than your obvious talent.

I am happy to hear I am somewhat of a role model for you and I hope that because of that you will pay close attention to what I am telling you.

The music business doesn't give a shit about you, or any of us. They will prostitute you for all you are worth, and cleverly make you think its what YOU wanted.. and when you end up in rehab as a result of being prostituted, 'they' will be sunning themselves on their yachts in Antigua, which they bought by selling your body and you will find yourself very alone.

None of the men oggling you give a shit about you either, do not be fooled. Many's the woman mistook lust for love. If they want you sexually that doesn't mean they give a fuck about you. All the more true when you unwittingly give the impression you don't give much of a fuck about yourself. And when you employ people who give the impression they don't give much of a fuck about you either. No one who cares about you could support your being pimped.. and that includes you yourself.

Yes, I'm suggesting you don't care for yourself. That has to change. You ought be protected as a precious young lady by anyone in your employ and anyone around you, including you. This is a dangerous world. We don't encourage our daughters to walk around naked in it because it makes them prey for animals and less than animals, a distressing majority of whom work in the music industry and it's associated media.

You are worth more than your body or your sexual appeal. The world of showbiz doesn't see things that way, they like things to be seen the other way, whether they are magazines who want you on their cover, or whatever.. Don't be under any illusions.. ALL of them want you because they're making money off your youth and your beauty.. which they could not do except for the fact your youth makes you blind to the evils of show business. If you have an innocent heart you can't recognise those who do not.

I repeat, you have enough talent that you don't need to let the music business make a prostitute of you. You shouldn't let them make a fool of you either. Don't think for a moment that any of them give a flying fuck about you. They're there for the money.. we're there for the music. It has always been that way and it will always be that way. The sooner a young lady gets to know that, the sooner she can be REALLY in control.

You also said in Rolling Stone that your look is based on mine. The look I chose, I chose on purpose at a time when my record company were encouraging me to do what you have done. I felt I would rather be judged on my talent and not my looks. I am happy that I made that choice, not least because I do not find myself on the proverbial rag heap now that I am almost 47 yrs of age.. which unfortunately many female artists who have based their image around their sexuality, end up on when they reach middle age.

Real empowerment of yourself as a woman would be to in future refuse to exploit your body or your sexuality in order for men to make money from you. I needn't even ask the question.. I've been in the business long enough to know that men are making more money than you are from you getting naked. Its really not at all cool. And its sending dangerous signals to other young women. Please in future say no when you are asked to prostitute yourself. Your body is for you and your boyfriend. It isn't for every spunk-spewing dirtbag on the net, or every greedy record company executive to buy his mistresses diamonds with.

As for the shedding of the Hannah Montana image.. whoever is telling you getting naked is the way to do that does absolutely NOT respect your talent, or you as a young lady. Your records are good enough for you not to need any shedding of Hannah Montana. She's waaaaaaay gone by now.. Not because you got naked but because you make great records.

Whether we like it or not, us females in the industry are role models and as such we have to be extremely careful what messages we send to other women. The message you keep sending is that its somehow cool to be prostituted.. its so not cool Miley.. its dangerous. Women are to be valued for so much more than their sexuality. we aren't merely objects of desire. I would be encouraging you to send healthier messages to your peers.. that they and you are worth more than what is currently going on in your career. Kindly fire any motherfucker who hasn't expressed alarm, because they don't care about you.

Here is complete text of second letter posted on O'Connor's official Facebook page:

ANOTHER OPEN LETTER TO MILEY CYRUS

Miley... Really? Who the fuck is advising you? Because taking me on is even more fuckin' stupid than behaving like a prostitute and calling it feminism. You have posted today tweets of mine which are two years old, which were posted by me when I was unwell and seeking help so as to make them look like they are recent. In doing so you mock myself and Amanda Bynes for having suffered with mental health issues and for having sought help.

I mean really really... who advises you? have you any idea how stupid and dangerous it is to mock people for suffering illness? You will yourself one day suffer such illness, that is without doubt. The course you have set yourself upon can only end in that, trust me.

I am staggered that any 20 yr old woman of the 21st century could behave in such a dangerous and irresponsible manner as to not only send the signal to young women that its ok to act like prostitutes but also to the signal that those who have suffered or do suffer mental health problems are to be mocked and have their opinions invalidated. Have you no sense of danger at all? or responsibility? Remove your tweets immediately or you will hear from my lawyers. I am certain you will be hearing from all manner of mental health advocacy groups also. It is not acceptable to mock any person for having suffered.

It is most unbecoming of you to respond in such a fashion to someone who expressed care for you. And worse that you are such an anti-female tool of the anti-female music industry. I hope that you will apologise to Amanda Bynes and to any person who has been wounded by your mockery of those who have suffered. And I hope that you will wake up and understand that you in fact are a danger to women.

Furthermore you posted a photo of me tearing the pope's photo .. as if to imply insanity.. by doing so all you have achieved is to expose your staggering ignorance. I suggest you read The Philadelphia Report, The Boston Report, all the reports which will illuminate for you why that action of mine remains sane and valid. By mocking it you mock every child who suffered sexual abuse at the hands of priests and had it covered by the Vatican. You could really do with educating yourself, that is if you're not too busy getting your tits out to read.

Here is complete text of third letter posted on O'Connor's official Facebook page:

Third letter to Miley

Miley

I have no interest whatsoever in meeting you. You had plenty of time yesterday to abuse Amanda Bynes .. an entirely innocent party.. and myself.. who also did nothing to deserve your abuse.. along with every other sufferer of mental health problems and every person who suffered abuse at the hands of priests.

You can take five minutes today between g- string fuckin' changes to publicly apologise and remove your abusive tweets. If you do not then you don't give a shit who you mock and what damage you do by being so ignorant.

When you publicly apologise to Amanda and myself and all mental health sufferers as well as all who were abused by priests that will end the matter as far as I am concerned.

what you did yesterday was designed to damage me and my career and has caused me enormous distress and harassment and has potential to damage my career, since you deliberately gave the impression those tweets of mine were not two years old but reflect my current condition. If you cannot apologize I will have no choice but to bring legal proceedings against you since it is extremely hard to be given work when people think one is suffering from mental illness.

I have no interest in or desire to cause you trouble but if you do not apologise for having deliberately tried to cause me hurt and trouble personally and professionally I will have to bring pressure upon you.

When you end up in the psych ward or rehab I'll be happy to visit you.. and would not lower myself to mock you.

Be a proper woman and make the public apologies I have listed above. Your hosting SNL is a bullshit reason for not taking five minutes to do the right thing and your behaviour yesterday will rebound upon you very badly.

You have no business abusing Amanda Bynes or anyone else. How do you think you made her feel yesterday? How do you feel when your friend Britney Spears is mocked and humiliated for having had mental health problems? I know I personally want to bash those who treat her that way. If she is your friend and more importantly if you are a true friend to her.. you ought apologise for joining those who mock and humiliate women who have been too nice frankly, to manage the music business without sensibly losing their minds.

Cease behaving in an anti-female capacity. You will become the victim of it shortly. Soon it will be you the media 'crazy' .. and you will not enjoy it.. and you will appreciate people (like myself) standing up for you. Which I will be happy to do.. if you earn my respect today by apologising publicly.