SABMiller and Molson Coors have announced that their joint venture in the US and Puerto Rico is now open for business.

The two brewers, who confirmed their alliance in the two countries in October last year, has seen MillerCoors commence trading today (1 July).

The new unit, which saw pro forma combined sales for the year to the end of March of US$7bn, will see each side hold a 50% voting interest in the joint venture and have five representatives each on its board. Based on the economic value of the contributed assets, SABMiller will have a 58% economic interest in the joint venture and Molson Coors will have a 42% economic interest.

"MillerCoors will be entrepreneurial, with the ability to operate with speed and agility in the marketplace, backed by the powerful combined resources of two exceptionally successful companies," said Leo Kiely, MillerCoors' chief executive. "We will drive profitable growth and bring new energy to the US beer industry."

The company will initially focus on delivering on the US$500m in identified annualised cost synergies by improving sourcing across its eight major breweries, building a streamlined organisation and leveraging the scale of the new company, Kiely added.

"Our talented people are experienced and passionate about this business and - importantly - are determined to win."