Cumbernauld-based Irn-Bru maker A.G. Barr came out fighting on Wednesday after news from PepsiCo Inc that it agreed to buy Rockstar Energy Beverages for $3.85 billion.

“A.G. BARR has been a franchise partner of Rockstar since 2007 and retains the exclusive distribution rights for the Rockstar brand in the UK, Ireland and certain European territories,” said the Scottish firm.

“A.G. BARR has a long term contract, extending for several years, for the manufacture and sale of the Rockstar energy brand, which contributes approximately 8% of the group’s sales volumes.”

PepsiCo has been a distribution partner for Rockstar in North America since 2009.

Announcing the deal, PepsiCo CEO Ramon Laguarta said: “As we work to be more consumer-centric and capitalize on rising demand in the functional beverage space, this highly strategic acquisition will enable us to leverage PepsiCo’s capabilities to both accelerate Rockstar’s performance and unlock our ability to expand in the category with existing brands such as Mountain Dew.

“Over time, we expect to capture our fair share of this fast-growing, highly profitable category and create meaningful new partnerships in the energy space.”