Miley Cyrus has been teasing a new song called ‘Used To Be Young’.

Several posters were spotted in Brussels featuring the new lyric: “I say I used to be young.”

As well as the new lyric, there were lines from her hits 'Party in the USA', 'Wrecking Ball', and 'The Climb'.

Over on YouTube, all the 'Flowers' hitmaker's videos have changed covers to read 'Used To Be Young'.

And in a recent interview with Vogue, the 'Midnight Sky' singer shared an extended version of the lyric from the track.

She recited: “I know I used to be crazy.

“I know I used to be fun. You say I used to be wild. I say I used to be young.”

And she's also posted exactly the same in a caption of a clip of the posters with cars speeding by.

Last week, Miley announced the 10th anniversary edition of 'Bangerz'.

And teasing new music, she wrote in the description: "Take a trip down memory lane to when Miley Used To Be Young."

A release date is yet to be announced.

Miley released the album 'Endless Summer Vacation' in March.

Meanwhile, Miley was recently in the headlines after the late Sinead O'Connor's open letter to the star resurfaced.

She warned the 'Malibu' singer not to be “pimped” by the music industry in the note on her website after Miley told Rolling Stone magazine she had been inspired by Sinead’s visuals in her iconic ‘Nothing Compares 2 U’ video when she made her music promo for her ‘Wrecking Ball’ hit, which saw her swinging without her clothes on from a demolition crane.

Sinead said in her message to the singer she was writing to her “in the spirit of motherliness and with love”.

She added to Miley it wasn’t "cool to be naked and licking sledgehammers in your videos”.

Her letter stated: “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 it’s the music business or yourself doing the pimping.”

She added in the note: “The music business doesn’t give a s*** 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 ogling you give a s*** about you either, do not be fooled.”

The pair were locked in a feud and Sinead even threatened legal action after Miley re-posted old tweets.

Miley had re-shared tweets about Sinead looking for a mental health facility and captioned it: "Before Amanda Bynes… There was…"

Sinead responded that she "mocked" her and Amanda Bynes for struggling with their mental health.

Miley had reacted to the letter: "Sinead. I don’t have time to write you an open letter cause I’m hosting and performing on SNL [Saturday Night Live] this week. So if you’d like to meet up and talk lemme know in your next letter."

And Sinead responded: "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.

"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."