STOCKHOLM • Sweden's legendary disco group Abba announced a reunion to record two new songs, 35 years after their last single, sparking joy and surprise among fans.

"We all four felt that, after some 35 years, it could be fun to join forces again and go into the recording studio. So we did," the group said in a statement last Friday after repeatedly vowing that they would never reunite.

The new songs I Still Have Faith In You and Don't Shut Me Down were recorded last summer, band manager Gorel Hanser told TT news agency.

The quartet split up in 1982 after dominating the disco scene for more than a decade with hits such as Waterloo, Dancing Queen, Mamma Mia and Super Trouper.

"It was like time had stood still and that we only had been away on a short holiday. An extremely joyful experience!" said band members Agnetha Faltskog, Bjorn Ulvaeus, Anni-Frid Lyngstad and Benny Andersson.

The members of the group, which sold more than 400 million albums, have not sung together publicly since 1986.

The stunning announcement came as Sweden was mourning the death of another of its music sensations, Avicii, one of the world's most successful DJs, whose real name was Tim Bergling.

He was found dead a week ago in Oman, where he had been on holiday with friends.

Computerised avatars are to perform I Still Have Faith In You in a TV special produced by NBC and the BBC to be broadcast in December, the group said.

It said the "exciting Abba avatar tour project had an unexpected consequence".

"We have come of age, but the song is new. And it feels good."

Ulvaeus, 73, was married to Faltskog, 68, and Andersson, 71, was married to Lyngstad, 72.

The group dominated the 1970s disco scene with its glitzy costumes, kitsch dance routines and catchy melodies.

It first found global fame after winning the Eurovision Song Contest in 1974 with the song Waterloo.

Mr Richard Skold, a 46-year-old Abba fan who works at a Stockholm book store, jumped up with surprise after hearing the news.

"This is the craziest thing I've heard! I never thought this would happen. And the fact that they're all still alive is fantastic!" he told AFP.

"BREAKING: ABBA have reformed. This may be bigger than Korea," British journalist and TV personality Piers Morgan tweeted, in a reference to last Friday's historic meeting between North Korean leader Kim Jong Un and the South's President Moon Jae In.

AGENCE FRANCE-PRESSE