NEW YORK -- Costco says it struck a deal for Citi to be the exclusive issuer of its co-branded credit cards in the U.S., with Visa replacing American Express as the card network.

The deal is subject to Citi buying the company's co-branded credit card portfolio, Costco said.

Costco and American Express ended their partnership after failing to reach an agreement on renewal terms. American Express said earlier this month that the relationship, which goes back 16 years, is set to expire March 31, 2016. Costco says the deal with Visa and Citigroup Inc. would take effect the next day.

The company said it would provide its customers with information about the transition in coming months.

Costco has been accepting MasterCards at its Canadian locations since Jan. 1, and recently signed an agreement to offer members a co-branded MasterCard with Capital One after ending its 15-year relationship with American Express.

Costco Wholesale Corp., based in Issaquah, Washington, has 474 locations in the United States and 88 in Canada.