The global super-rich may have as much as $3.55tn hidden away from tax authorities, according to estimates by Oxfam.

The charity renewed its call for a wealth levy and urged governments to close tax loopholes as it published its latest analysis of the scale of offshore holdings.

Building on the work of academics including the French economist Gabriel Zucman and the EU Tax Observatory, Oxfam said total wealth held offshore had increased significantly, to $13.25tn (£10tn) in 2023 – the latest year for which estimates were available.