United Trust Bank has secured an investment from private equity firm Warburg Pincus, which will take a minority stake in the lender.

Subject to regulatory approval, the agreement will help to fund UTB’s expansion and allow it to branch into new product areas.

The investment amount has not been disclosed, but it values the bank at around £520m.

UTB was formed in 1955 to provide development finance to small and medium-sized housebuilders that were tackling the post-war housing shortage.

In 2001 it was bought by Anglo-Dutch bank, Insinger de Beaufort.

UTB’s current chief executive, Harley Kagan, and deputy chairman, Graham Davin, led that acquisition 23 years ago.

Warburg Pincus has invested more than $25bn across 60 companies globally, with a particular focus on specialist banking and lending.

Kagan says: “This is an exciting milestone for UTB and an excellent opportunity for our staff, shareholders and for Warburg Pincus.

“I am delighted that Warburg Pincus will be joining us as a new partner to help accelerate our growth and provide support and experience as the group heads for a £4bn balance sheet and explores exciting new products and markets in the future.

“It just remains for me to say that the growth story over the last 20 years would not have been achievable without the exceptional UTB staff who work carefully every day to build the Bank and deliver outstanding products and services to our customers, and for that we wish to sincerely thank them.”

Warburg Pincus managing director Mike Thompson says: “We look forward to working closely with Harley and his team to support the Bank’s continued growth and leveraging the expertise of our financial services and capital solutions teams to help the company seize new opportunities in the UK market.”