O’Neill is the third-longest serving manager in the UK running an open-or-closed-ended fund, having run the portfolio for 30 years.

He will retire as lead manager at the end of January, with Wouter Volckaert, who has recently joined Henderson’s specialist Global Equities Team, taking over the trust.

Volckaert is an investment manager in the Henderson Global Equities team currently, having joined Henderson from Morgan Stanley, where he managed concentrated and diversified global equity portfolios for both institutional and retail investors.

Prior to this, Wouter worked at ABN AMRO Asset Management as a global equity portfolio manager.

Volckaert said: “I’m immensely proud to be following in the footsteps of one of the industry’s longest serving and best known portfolio managers, and am very grateful to Brian for his advice, guidance and support in the transition process.

“The Trust is in great shape and I look forward to carrying on working with Henderson’s wider global equities team to achieve the Trust’s objectives, and complete Brian’s ambition to make this a truly global portfolio.”