The move leaves Morison KSi looking for one or more new UK members.

Morison KSi said Kingston Smith’s decision was ‘purely based on commercial reasons’.

Amanda Long, CEO at Morison KSi, said: ‘We are sorry to see Kingston Smith leave the association but relationships between both parties remain very good. We will be prioritising the recruitment of one or more high quality UK member firms and look forward to the opportunities that this will bring to the association and our members.’

Morison KSi has 154 members across 82 countries worldwide.

Ranked at number 20 in the Accountancy Daily Top 75 league table of UK accounting firms, Kingston Smith now becomes  the main London-based firm of the Moore Stephens International network of more than 260 firms in 112 countries.

With 62 partners and 550 staff, Kingston Smith posted fee income of £51.7m last year.

Anton Colella, global CEO of Moore Stephens International, said: ‘I am delighted to welcome Kingston Smith to our network. They are a firm with a justifiably strong reputation not only in London – one of the world’s main capital markets – but also internationally.

‘Their demonstrable strength in sectors such as financial services and media, will complement our network’s existing capabilities.’

Maureen Penfold, managing partner, Kingston Smith, said: ‘Joining Moore Stephens International is a natural next step for us in supporting our clients to reach their potential for international expansion.

‘Being a part of this powerful global network will bring considerable benefits to our clients, enabling us to offer a fully integrated service to support their growth consistently across the world.

‘We are equally excited about the new opportunities it will bring to our people, as we will be able to offer enhanced global mobility and greater collaborative knowledge sharing on an international scale.’

Pat Sweet