Spain's Santander is preparing to raise part of the debt financing it needs to support the purchase of its stake in Dutch bank ABN Amro with the sale of close to $9bn (€6.3bn) worth of subordinated bonds across three separate tranches.

The sale, which comes after the Spanish bank met institutional investors in the UK and Europe, could be wrapped up this week by the eight lead underwriting banks after they opened the order books on the euro and sterling tranches yesterday.