The plans affect how mortgage instalments will be calculated, introduces interest-free repayments on some instalments, urges banks to increase interest on deposits and will make banks pay into a new stability fund.

"There is still so much uncertainty and unknowns that today it is really difficult to assess what impact this will have on the banking sector," Santander Bank Polska Chief Executive Michal Gajewski told journalists.

"I think we should still wait and see in which direction these solutions will go," he said, adding that he hoped banks would be able to take part in shaping the new regulations.

(Reporting by Karol Badohal and Mateusz Rabiega; Editing by Edmund Blair)