The Wealth Management Association (WMA) believes the vote will now lead to a “prolonged period of uncertainty”.
The organisation said in a statement: “It is important that there is a focus on long term investment ensuring the continued success and stability of the UK’s £734bn wealth management community for the country and its clients.
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“WMA will be working with our member firms to assist them to meet the challenges that will arise from the referendum result.
“During the time in which our new relationship with the EU is being determined our member firms will still be subject to both UK and EU law and we will continue to work closely with both UK and EU authorities, regulators and government.”
The Investment Association, which represents trust and investment fund managers, called for the industry to “adopt a collective long-term focus on how the UK can preserve the pre-eminence of its financial services sector including our highly successful £5.5 trillion asset management industry – the second largest industry of its kind in the world”.
The body said: "How the UK's role in the EU will change will become clearer over time, but there are likely to be challenges ahead and we look forward to helping the Government and our industry to navigate these.
"The Investment Association is confident our industry will be able to continue to compete overseas, both in the EU and the rest of the world. Our objective remains to play a positive role within the UK economy as a source of funding for companies, a major contributor to export earnings and as a centre of investment excellence that serves both domestic and overseas clients successfully."