Goerlich MADRID/VIENNA (Reuters) -Erste Group Bank has bought a 49% stake in Santander's Polish bank for around 6.8 billion euros ($7.7 billion), turning Austria's largest lender into one of the most important banks in Poland and freeing up billions for Santander.

Erste Group Bank AG agreed to buy much of Banco Santander SA’s operations in Poland for about €7 billion ($7.9 billion), marking its largest deal ever.

Spanish banker Ana Botín, executive chair of Santander Group since 2014, confirmed via social media that Santander has agreed to sell 49% of its Polish banking subsidiary, Santander Bank Polska, and 50% of its Polish asset management arm to Austria’s Erste Group.