Santander of Spain, the eurozone’s biggest bank by market capitalisation, on Monday unveiled details of a $6.4bn-$7.3bn share offering by its Brazilian subsidiary, confirming predictions that the issue would be one of the largest initial public offerings in the world this year.

In a regulatory filing in Madrid, Santander said it planned to sell 525m Brazilian and US-listed units composed of underlying ordinary and preference shares and amounting to 16.21 per cent of the current capital, or 13.95 per cent of the post-offer capital, of Banco Santander (Brasil).