Walmart spokeswoman Marilee McInnis said in a statement that the company is "disappointed CVS chose not to come to a resolution in a way that is beneficial to their members who are also our customers." McInnis also said that the retailer wants to pass along savings to their customers, not a middle man.
For its part, CVS is placing the blame for the split on Walmart.
"At a time when everyone is working hard to find ways to reduce health care costs, Walmart's requested rates would ultimately result in higher costs for our clients and consumers," said Derica Rice, president of CVS Caremark, in a statement.
Rice's statement also said that CVS could not agree to Walmart's demands for an increase in reimbursement.
CVS said that it has asked Walmart to stay in its networks through April 30. A person familiar with the matter told the Wall Street Journal, which first reported the story, that the split could come as early as next month if Walmart doesn't agree.
Walmart said that it is still trying to find a solution that would benefit both parties and their shared customers.
CVS Caremark, the pharmacy-benefits arm of CVS Health, said that if a split happens, it would not affect the pharmacy networks in its Medicare plans. Sam's Club stores would also be spared from any impact.