The Clayton-based maker of Zhu Zhu Pets said Friday that it was "troubled" by recent comments from a Build-A-Bear Workshop executive in reference to the retailer's decision to discontinue selling the robotic hamsters because of lower-than-expected sales in its stores.

"We believe the sales performance Zhu Zhu Pets experienced at Build-A-Bear Workshop is wholly unrelated to the overall health of Zhu Zhu Pets as a brand and is more a reflection of ongoing issues that Build-A-Bear is facing," Russ Hornsby, the chief executive of Cepia LLC, said in a statement.

He added that Cepia stopped all shipments to Build-A-Bear as of April 26 because of an "ongoing payment dispute." But he did not elaborate.

A Build-A-Bear spokeswoman said Friday evening that she was unable to comment.

In a conference call with inventors Thursday, John Haugh, the president of Overland-based Build-A-Bear Workshop, said that the roll-out of Zhu Zhu Pets to all of its stores had not been going as well as hoped amidst competitive pricing and that the company would stop selling the line.

"The line overall is under significant competitive pricing pressures that are somewhat unprecedented for a hot toy so early in its life cycle," Haugh told investors.

He said Build-A-Bear would reduce the prices on the hamsters in order to move the inventory from its stores by the end of the year.

In the conference call, Build-A-Bear also reported lower-than-expected second-quarter results in which it had a loss of $8.5 million. The company blamed part of the weak performance on an early Easter that fell into the first quarter.

In Cepia's statement, Hornsby noted that Zhu Zhu Pets continue to sell well globally at all major toy retailers. And he said that industry sources, including the NPD group, have said it is the No. 1 plush-toy brand in the world.

Zhu Zhu Pets are also sold at many large retailers such as Walmart, Toys R Us and Target.