The Swedish music legends, famed for hits including Mamma Mia, Dancing Queen, Super Trouper and Take A Chance On Me, confirmed in April they were going back to work.
Pictures show Bjorn Ulvaeus, Benny Andersson, Agnetha Faltskog and Anni-Frid Lyngstad working their magic in a Swedish recording studio.
The band were laying down two long-awaited new songs to be released later this year. Their first, I Still Have Faith In You, should be out in December.
In one snap Bjorn and Benny look deep in thought at a mixing desk in the Stockholm studio, while in another Agnetha and Anni-Frid tried out their vocals.
The pictures sent fans wild with one, Gerard Hayes, saying: “The circle is complete now for Abba and their fans. These are pics we have all dreamed of.”
Another Trevor Ashman said: “I bet they will be the Christmas number ones.” The group, formed of two married couples, Agnetha and Bjorn, and Benny and Anni-Frid, won the Eurovision song contest with Waterloo in 1974 and went on to become one of the most popular in history, selling over 380 million albums and singles worldwide.
In 1982 they announced they were “on a break” following the demise of both marriages. They finally called it a day in 1983.
The band said their getting back together was a consequence of the decision 18 months ago to put on a “virtual reality tour” next year.
The songs will be performed by digital avatars of the group from their 1970s heyday.
Earlier this year the group said: “The decision to go ahead with the exciting avatar tour project had an unexpected consequence. We all four felt that, after some 35 years, it could be fun to join forces again and go into the recording studio.
“It was like time had stood still and that we had only been away on a short holiday.”
Benny and Bjorn are also enjoying a revival of their musical Chess, which opened in London’s West End last month to rave reviews.