Coffee manufacturers are being forced to increase their prices because of the soaring cost of robusta and arabica coffee beans.

Kraft Foods, owner of the Maxwell House brand, has increased the price of its coffee by 4% after wholesale coffee prices hit their highest levels in more than a decade, according to the Financial Times.

“The wholesale price of coffee beans has increased significantly since the beginning of 2008, due to a combination of the weak US dollar and a dramatic increase in speculative investments in commodities, including green coffee,” a spokesman told the paper.