Rebecca Ferguson sued by former managers

Image caption, Ferguson's debut album, Heaven, reached number three in the charts

Soul singer Rebecca Ferguson is being sued for breach of contract by her former managers.

The X Factor runner-up split from Modest Management Ltd in June.

She later described them as "vile" on Twitter, saying they had forced her to conduct interviews after she collapsed with exhaustion.

Modest has filed a High Court writ, asking for a declaration that the star unlawfully ended her contract and seeking 20% of her future earnings.

In legal papers filed in London, a lawyer for the company said Ferguson initially signed a five-year management contract "on or about 15 October 2010".

Ian Mill QC contends she then sought to terminate the relationship in June 2012, citing an email from the singer as proof.

"I am really unhappy with how I have been treated by you over the last couple of months and how miserable I have become," the email is quoted as saying.

"The deterioration of my health has not been relevent [sic] to you until this week when it reached another low point.

"I have lost all faith and trust in you as managers so I have no option but to terminate our working relationship with immediate effect."

The company's lawyers then wrote to Ferguson on 25 June 2011, saying it accepted her "renunciation and repudiation of the management agreement".

According to the court papers, Ferguson wrote back saying she "did not accept" this interpretation of events.

Modest is now seeking a ruling on the matter, as well as damages and a percentage of Ferguson's earnings during the remaining term of the contract.

The dispute first came to light on 13 July when Ferguson tweeted a series of messages voicing her anger at the company, which also represents fellow X Factor recording artists Leona Lewis, Olly Murs, Little Mix and One Direction.

She they had "watched me collapse [then] gave me a can of Coke and said now go do your interview."

"I need to see my children you need to give me time off vile!!!!" .

A added: "Be nice to have a nice new responsible caring management team!! Who care for me and my childrens well being #seeyouincourt!!!"

Ferguson is no longer listed as a client on the company's .

After news of the court case came to light, the singer released a statement to her fans.

"All I want to say is I am happy, I am well and I am focused on work," the 26-year-old wrote.

"I've lost many friends and many people around me. Fame comes with good and bad."

"My voice is a gift... and it's my choice what I do with it. I came into this industry, and I'll leave this industry, with a few things: My dignity, my honesty and my love for music."

Ferguson played Radio 2's Live in Hyde Park concert on Sunday and has been tipped as a potential nominee for this year's Mercury Prize.