Shares in K-Swiss Inc. sunk more than 3 percent Friday after a Banc of America Securities analyst started coverage of the athletic shoemaker and rated it a “sell,” saying the company is still facing challenges in its international business.

Banc of America Securities analyst Robert Ohmes said the Westlake Village company’s international segment, which has accounted for more than 50 percent of its total sales so far this year, will begin to slow and may no longer compensate for the company’s sluggish U.S. sales.

Ohmes said the brand is only in three countries in Europe and that K-Swiss has been slow to expand its presence. But Ohmes said that the shoe maker’s efforts in China offer a promising long-term opportunity, though international growth will stall through next year.

Shares in K-Swiss dropped 85 cents, or 3.3 percent, to $25.10 in afternoon trading Friday on the Nasdaq.