Sean – who founded the company and will remain on the board as a non-executive director – will be replaced as CEO by Martin Bischoff, subject to regulatory approval.

Martin has previously served as managing director of retail distribution at Santander and will lead Castle Trust as it looks to apply for a banking licence.

Sean founded Castle Trust with backing from JC Flowers & Co in 2011 and said that he was incredibly proud of building the company from scratch into a sustainable business.

“As we prepare to move from being a speciality finance provider into a bank, it is an appropriate moment for me to consider a new challenge for the next stage in my professional career.

“I am looking forward to continuing to play a part in Castle Trust's development as a non-executive director.

“I am also keen to maintain the very strong partnership that I have built with JC Flowers & Co, who have been such supportive shareholders and business partners in the growth of Castle Trust and are underpinning the company's move to become a bank.”

Sean said that Martin was a seasoned retail banking CEO and was steeped in the experience required to build and scale a successful retail banking operation.

“I have the greatest confidence in his ability to lead the business from strength to strength.

“Handing the reins over to Martin will allow the business to benefit from an experienced retail banker to lead the business in its next phase and allow me to move on to establish a credit-focused investment manager, which plays to my personal strengths and experiences.”

Martin added: “I am enthusiastic about joining at this exciting moment in the history of the company.

“Castle Trust has a bright and secure future as it grows its specialist lending businesses that we can all be proud of and committed to.”

Tim Hanford, managing director in charge of JC Flowers & Co Europe, said that it had enjoyed playing its part as major shareholders in creating a strong business and was excited that Castle Trust was now ready to take the next step and apply for a banking licence.

“Sean is a natural entrepreneur and we understand his desire to start a new venture.

“We wish him every success with his new business and look forward to continuing to benefit from his experience on the board.

“Looking forward, we are excited about Martin Bischoff joining the team, and have every confidence that he will build on the existing platform to take Castle Trust to continued success.”