Abba star Agnetha Faltskog was initially reluctant to launch a career comeback because she feared her voice would be too weak.

The Swedish star went back to the studio last year (12) with famed songwriter Jorgen Elofsson to work on her first album of new material since 1987, A, which is due for release in May (13).

Faltskog hadn't sang professionally for nearly a decade when she started work on the project, and told Elofsson she would give up on the album if her voice didn't sound good enough.

She tells the Bbc, "I told him, 'We have to talk about a lot of things first'. It was nine or 10 years since I'd sung, so I didn't know if (my voice) worked. I said from the beginning, 'If it sounds old I don't want to do this, because... Why should I?'"

The album includes a duet with British pop star Gary Barlow, I Should Have Followed You Home, but Faltskog reveals they sang their parts separately and have never met.

She adds, "We haven't even met. I spoke to him once on the phone - but I was on holiday when he did his singing."

Faltskog's last release was a 2004 collection of 1960s covers called My Colouring Book.