Diageo is trying to overturn a new German tax as a crackdown on underage drinking across Europe threatens sales of its Smirnoff Ice vodka cocktail.
In recent months, Germany, France, Switzerland and Norway have all agreed, or implemented, laws to increase the tax on sugary, pre-mixed cocktails.
The drinks industry calls these products "RTDs", or ready-to-drinks, and successful brands have included Smirnoff Ice and Bacardi Breezer.
However, in the UK, where such drinks are best-established, they are often dismissively referred to as "alcopops" because of their appeal to younger palates, a term which has caught on in Germany.
The British government has already shown how tax rises can stifle demand for RTDs. It increased the duty rate in 2002, citing concerns about binge drinking, and price-sensitive drinkers bought fewer bottles.
Although RTDs are now seen as a waning phenomenon in the UK, the market is at a much earlier stage elsewhere in Europe.
The German tax rise came into force this month.
Diageo asked the federal constitutional court in Karlsruhe to block the law immediately. Although the request was denied, Diageo said the court had agreed to review the legislation.
The London-based group denied RTDs appealed to the young or stimulated binge drinking. It said it was considering legal challenges in other countries that had raised RTD taxes.
