USA &#8211, The government confirmed this week that it has stocks of milk powder worth $1 billion (&#8364,1 billion), which it has bought to maintain milk prices over the last three years.

The stocks are kept in bags in privately owned man-made caves in Montana and in warehouses around the country. More than 10 million kilograms are added to the stocks each week.

The Department of Agriculture is required to buy supplies of butter, cheese and milk powder to maintain milk prices. The scheme was supposed to end in 1999, but it was temporarily extended. It was then made permanent again in a new farm bill in May.

Processors continue to sell the powder in this way rather than converting it into proteins because the government pays more for the powder than processors can fetch for protein products.

Storage of the powder costs the government of the USA around &#8364,20 million per year.