benny andersson and bjorn ulvaeus for most of them in your studio near stockholm. great as we thought were great. reporter: in 1972 benny andersson and his girlfriend teamed up with bjorn and his partner to form abba. they toured the world, but when the relationships broke up, so did abba. the band ceased to exist in 1982. fans have always dreamt of a reunion, and hopes were reignited when in 2016, the four members appeared on stage and sang at an invitation-only event. now that have reunited in the studio, the question is whether they will perform together live. >> ♪ feeling like a number one brent: and here is a reminder of the top story we are following for you. germany's chancellor angela merkel has met with u.s. president donald trump to discuss trade, but despite it warmer atmosphere, there were unable to overcome differences on the iran nuclear deal. after a short break, i will take you through the day. korean peace, trump and merkel, and knowing me, knowing you again. [captioning performed by the national captioning institute, which is responsible for its c