The chief executive of Royal Bank of Scotland has warned that the bank may have to shed a number of business customers if there is no Brexit deal.
Ross McEwan said 150 RBS staff had been deployed to Amsterdam to set up a new operation serving the bank's European customers ahead of a no-deal scenario.
He said the bank was "preparing for the worst" and was still awaiting final approval on licences for the operation.
The UK is on course to leave the EU in March next year.
Prime Minister Theresa May has said she is confident of striking a deal with the European Union over a future trade relationship.
However, the UK government has also been preparing for a no-deal scenario amid growing concern about the potential disruption to financial markets if no deal is reached.
In an interview with BBC Scotland, Mr McEwan said: "We are planning, unfortunately, for the worst.
"If there is no agreement and we fall out of Europe, we have to be ready for our customers.
"So we're setting up an operation in Amsterdam, awaiting final approval for the correct licences.
"We're having to put a number of our senior team and our systems and processes to move our European customers across into that entity for our markets business and our corporates.
"If we don't get the right licences, and we don't get them in time, that could create major problems for our customers and for the bank."
Mr McEwan said that if the bank failed to secure trading licences for its Amsterdam operation, it would be unable to provide services to some of its European customers.
He added: "In the next couple of months, we're going to have to make some decisions, to make sure we've got the licences and if we don't, we're going to have to think about which European customers we may not be able to bank."