The euro's slide in value against the U.S. dollar this year will have a "relatively minor" impact on U.S. companies with earnings tied heavily to European economies, Fitch Ratings said in a report.

That includes iconic U.S. companies such as Coca-Cola Co., McDonald's Corp., Pfizer Inc. and Hewlett-Packard Co.

Fitch said U.S. companies should be more concerned with "collateral damage" from the expanding debt crisis there and heightened credit concerns. The agency thinks that fiscal conservativeness might squash growth.

Also, if the euro stays weak it could further hurt U.S. companies' earnings and sales, and damage their ability to compete globally. But companies such as McDonald's that have designed programs to hedge their currency losses should be able to offset the losses, Fitch said.