Reports that economic sanctions against Russia "are likely to be imposed within days" must be making a number of American CEOs very nervous, as such a move could cut off companies from a major, growing market. Here’s a rundown on some of the biggest U.S. companies that could be impacted:

PepsiCo Company

Pepsi had nearly $5 billion in net revenue in Russia in 2012, accounding for 7.42 percent of their total net revenue, and the country also represents one of Pepsi’s fastest-growing markets. The company has been buying up Russian firms, including a $5.4 billion acquisition of the leading dairy producer in 2010.

Coca Cola Company

Coke does not disclose its net revenues in Russia, but still has a large presence there. In 2011, it reported 3 percent growth in beverage volumes in the country. In 2011, it partnered with a global bottler, Coca-Cola Hellenic, in which it owns a 23 percent stake, to invest $5 billion in Russia through 2016.