Marcos Martinez, chief executive of Spanish bank Santander in Mexico (R) gives a speech next to Emilio Botin, chairman of Santander, during a news conference at a hotel in Mexico City September 4, 2012. Spanish bank Santander said on Tuesday it would seek to raise up to 3.4 billion euros ($4.3 billion) through the stock market listing of a quarter of its Mexican unit as it looks to boost capital levels and weather a grinding recession at home. The euro zone's biggest bank said it would list 24.9 percent of Grupo Financiero Santander Mexico in what could be Mexico's biggest initial public offering ever, valuing the unit at up to 13.7 billion euros. REUTERS/Henry Romero (MEXICO - Tags: BUSINESS)