The group's first incarnation appear to be working on their forthcoming record with the singer after Keisha Buchanan posted an image of the pair in the studio.
Buchanan tweeted: "Great day in the studio with @KatyBmusic !!! The album is coming guys! Whooooooop (sic)"
Katy B later replied: "such a pleasure! see you soon!!!! xxx"
It was recently reported that the trio - consisting of Buchanan, Mutya Buena and Siobhan Donaghy - secured a £1m record deal with Polydor for their comeback.
Emeli Sandé has also been linked to the project, after she revealed: "I'm happy to kind of be involved in what started the whole Sugababes journey. It sounds amazing."
Watch Sugababes perform their debut single 'Overload' live below: