Swedish supergroup ABBA has announced its first new album in four decades and says it will stage a series of virtual concerts using digital avatars of themselves in London next year.

The album Voyage will come out on November 5, the band said during the streamed launch. It released two of its 10 songs – I Still Have Faith In You and Don’t Shut Me Down – on Thursday.

“First it was just two songs,” songwriter Benny Andersson said in a pre-recorded video message.

“Then we said ‘maybe we should do, I don’t know, a few others. What do you say girls?’ And it said ‘yeah’ and then I asked ‘why don’t we do a full album?'”

The recording went smoothly, co-songwriter Bjorn Ulvaeus said. “It all came rushing back in a matter of seconds.”

“I knew when Benny played the melody it just had to be about us,” he added about I Still Have Faith In You. The new album will also include a Christmas song Little Things.

The concerts will be held at a purpose-built ABBA Arena in London’s Queen Elizabeth Olympic Park in May, and feature digital versions of its four stars Agnetha Faltskog, Bjorn Ulvaeus, Benny Andersson and Anni-Frid Lyngstad.

The “abbatars” were created using motion capture technology – similar to that used to create Gollum in The Lord of the Rings movies series – and will show members of the band as they looked in 1979.

“The only big problem was that we had to shave our beards,” Andersson said.

The concerts will feature 22 songs, including the two new numbers and a “sort of a greatest hits” compilation, including Dancing Queen, he added.

ABBA was founded in the early 70s by then couples Agnetha and Bjorn, together with Benny and Anni-Frid. Their initials gave the band its name.

It sold more than 385 million albums and topped charts from Australia to America with a string of hits including Waterloo, The Winner Takes It All and Take A Chance On Me.

Its last album with fresh material, 1981’s The Visitors, included songs tinged with the sadness of their divorces. The band split a year later.

Rumours swirled for years that ABBA would get back together, but the members turned down many offers, including one reported $US1 billion ($1.4 billion) package to tour again.

-AAP