Citigroup Inc. (C) raised 2 billion Brazilian reals ($896 million) with the sale of a portion of its stake on the Brazilian credit card networking services provider Redecard SA (RDCD3.BR) through a secondary offer, Redecard said in a statement Wednesday.

Citigroup sold 82 million shares of Redecard on the Brazilian Stock Exchange, or Bovespa, with each share priced at BRL24.50.

The shares were sold in Brazil and also to foreign investors in the form of Global Depositary Receipts, or GDRs. Each GDR will represent two common shares.

The shares under the offer are set to begin trading Thursday.

Citigroup said it could increase the offer of Redecard's share if there is sufficient demand, offering an extra lot of 24 million shares. Citigroup is the lead coordinator of the operation.

Before the current operation, Redecard was jointly controlled by Brazilian banking giant Itau-Unibanco and Citigroup. Itau-Unibanco had a combined 46.42% stake in Redecard, while Citigroup had a 17% stake.

Earlier this week, Itau Unibanco announced that it exercised its option to acquire 24 million shares of Redecard, becoming the company's controller.

Itau-Unibanco was formed late last year by the merger of Itau (ITU), at that time Brazil's third-largest bank, and Unibanco (UBB), at that time the country's fourth-largest bank.

On Tuesday, Redecard's share closed up 1.41% at BRL25.05 on the Bovespa.

-By Rogerio Jelmayer, Dow Jones Newswires; 55-11-2847-4521; rogerio.jelmayer@dowjones.com