The singer has turned from opera to pop for her latest album

The 19-year-old said she was recently followed all evening by a man who took pictures with a camera phone while she was drinking with friends at a club.

She said he then tried to "blackmail" her for �15,000 by threatening to sell the photos to the papers.

Church, who is going out with Wales rugby star Gavin Henson, releases her first pop album in July.

Speaking to the BBC, the Cardiff-born singer who shot to fame as a classical-music singing 11-year-old, said the media's obsession with her private life and loves is becoming worse.

She told the Radio 4 arts programme, Front Row, that she had tried to maintain as normal a life as possible despite the media interest in her previous "bad choice of boyfriends".

Church says parts of her new album are autobiographical

She said: "Nowadays it's getting more and more difficult. It's getting a lot worse.

"I will probably have to get a bodyguard, which is not what I had before. I need it now.

"For a while I just had an 'I don't care' attitude, but I can't live like that any more."

In April, Church's mother Maria Church said her daughter becomes 'depressed' about the constant press pursuit over her private life.

Tabloid newspaper and gossip magazines have covered the teenager singer's break-ups with boyfriends Steven Johnson and Kyle Johnson.

Musically, the teenager is proud of her latest album, Tissues and Issues, the first in three years, released on 11 July.

She said she was involved in writing all the melodies as well as many of the lyrics, parts of which are autobiographical.

She said: "My musical knowledge is probably better than most pop singers because of what I have done in the past.

"I don't have a theme - my voice just links it all together, with a bit of luck."