London (CNN Business) Royal Bank of Scotland has taken a £100 million earnings hit over Brexit, making it the first major lender to acknowledge costs related to the divorce.

The bank said Friday that it took action because of the " more uncertain economic outlook ." Analysts said the move was designed to account for loans that may go bad following Brexit

"The risk of a disorderly Brexit has increased. We are not where we had wanted to be as a nation at this stage of the year," Katie Murray, the bank's interim chief financial officer, said during a conference call with investors.

Shares in RBS ( RBS ) dropped over 4% following the release of its quarterly earnings. Other UK banks such as Lloyds ( LYG ) and Barclays ( BCS ) did not set aside money for Brexit when reporting earnings this week.

The United Kingdom is scheduled to leave the European Union on March 29, 2019. But companies are still in the dark about what that means for their ability to do business across the new border.

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