Rockers Nightwish have drafted in a replacement singer to help them complete their ongoing world tour following the departure of frontwoman Anette Olzon.

Olzon joined the Finnish group in 2007 as a replacement for original vocalist Tarja Turunen and the musicians have confirmed she will no longer be a part of the band.

They have now drafted in former After Forever singer Floor Jansen to take her place so they can continue with their Imaginaerum world tour.

A statement posted on the Nightwish website reads, "Another chapter of the Nightwish story has ended today. Nightwish and Anette Olzon have decided to part company, in mutual understanding, for the good of all parties involved.

"In recent times it has become increasingly obvious that the direction and the needs of the band were in conflict, and this has led to a division from which we cannot recover.

"Nightwish has no intention of cancelling any upcoming shows, and as a result we have decided to bring in a substitute vocalist... her name is Floor Jansen from The Netherlands... and she has graciously stepped in to help us complete the Imaginaerum world tour.

"We are all strongly committed to this journey, this vehicle of spirit, and we are sure that this will lead to a brighter future for everyone."