Terms were not disclosed for the deal, which comes 22 years after the Spice Girls teamed up with Pepsi in the mid-1990s for a huge multi-faceted promotional campaign that spawned TV spots, special CD releases and concert ticket giveaways.
Other pop artists that have partnered with Pepsi over the years include Beyoncé, Nicki Minaj, One Direction, Madonna, Britney Spears, Kanye West, David Bowie, Michael Jackson, Tina Turner, Gloria Estefan and MC Hammer, to name a few.
"Pepsi has a unique track record in supporting new music talent, as they did when we first worked together on Spice Girls and are doing again with Now United," said Fuller in a statement.
He went on to say that the Pepsi brand and its "For the Love of It" campaign "reflects so many of the positive values which are present in Now United and I know they will inspire and enable the group and their global fan base to embrace their passions like never before."
Speaking to Billboard, Fuller said that Pepsi was the first company he approached when looking for brand sponsors for Now United. "This project is very ambitious and my vision for it is to do things differently and Pepsi as a company is also very ambitious and looks to do things differently.
"They are very connected to entertainment, music and sport and they want to be at the forefront of innovation. They are also very artist-friendly. They want to empower performers and that's what Now United is all about. The synchronicity and the symbiotic nature of this relationship really is as good as you could imagine."
Although exact details are yet to be revealed, Fuller says that Pepsi's deal with Now United -- which inked a sponsorship deal with business-to-business tech giant SAP last year -- will see the two parties create "unique and extraordinary events," music, video and digital content on a global basis throughout 2019.
One partnership that has already resulted from the Pepsi deal is a studio collaboration between Now United and Indian rapper Badshah on the song "How We Do It," recorded late last year following an introduction brokered by the drinks manufacturer.
Since its premier on Dec. 15, the song's video has had over 10 million views and helped launch the group in India.
"Now United, come the end of 2019, will be one of the biggest international acts in India," predicts Fuller. "And as we look around for new members from other countries, which is our focus right now, we will do it with Pepsi by our side and in ways that nobody has done before."