Lloyds Bank has warned that a vote to leave the EU would cause economic uncertainty and potential volatility.
Lloyds, which is the biggest lender of mortgages in the UK and one of Europe's biggest banks, said that the long-term impact of Brexit was unclear because it's impossible to say how the UK's position would change outside the union.
In a statement, Lloyds said: "The Board is mindful that the future of the UK's relationship with the EU is a matter for the UK electorate, and that for many the debate is about more than just economics,“ the bank's board said in a statement following a meeting to discuss the referendum on June 23.
“Lloyds Banking Group will maintain its focus on being the best bank for customers and shareholders, and will continue to support its customers, irrespective of the referendum outcome.”
The statement reflects an opposing view to that of Lloyds chairman Norman Blackwell, who told the House of Lords in October that there was no "compelling economic argument" for the UK to say in the EU.
"I do not agree that remaining in the European Union without a significant change in the current treaty arrangements is ultimately sustainable from a political and constitutional perspective," Lord Blackwell told the House.