Under the deal, Caixabank will sell 439 real estate units to a Spanish subsidiary of Mexico's Inmobiliaria Carso for 428 million euros. The lender will book gross capital gains of 200 million euros ($263.23 million).

Separately, the Spanish savings bank signed a sale and lease back deal with Inmobiliaria Carso with an option to buy back the property units.

Inmobiliaria Carso is part of the business empire of Carlos Slim, who already has close business ties with Caixabank.

Caixabank owns 20 percent in the Mexican financial group Inbursa, controlled by Slim, who in turn is a minority shareholder of the Spanish lender.

More deals in the property sector or on other portfolios, such as consumer loans, are likely to take place early next year, bankers in Madrid said earlier this week.

All Spanish banks have made provisions for losses on toxic real estate loans or foreclosed properties, which should help them withstand sales of these types of assets at big discounts, which many had so far been resisting.

Popular sold a 1.14 billion euro ($1.5 billion) portfolio of troubled consumer loans to a consortium of international investors last week with an estimated gross gain of 48 million euros.