The merger will be finalised on 1 January 2020 and will create a 257-strong group of member firms with revenues approaching $1bn (£780m), placing it in 16th position in the current global accountancy network ranking.

The network will be known as MGI Worldwide with CPA Associates International, with most firms rebranded under the double name. However, a few of the US members of CPAII will retain their original affiliation for the time being.

The deal was signed in Dubai, UAE, during MGI’s global annual general meeting at the end of October following a vote by members of both organisations.

The merger will offer member firms greater resources, access to more expertise in new jurisdictions, a wider range of services and stronger brand recognition. Global quality assurance will be available to CPAAI firms when they join the MGI Worldwide network.

The merger will draw on regional expertise, with CPAAI especially strong in the US, China and Mexico, and MGI Worldwide with a greater global reach.

Both organisations have been active for more than 60 years in their markets and combined will offer clients access to almost 9,000 professionals in almost 100 countries.

Clive Viegas Bennett, CEO of MGI Worldwide, said: ‘This merger greatly strengthens the already solid market positions of both organisations and the resources for our member firms.  Our new global and regional management team will be unbeatable.

‘For members, our coming together will bring a wide range of new benefits, access to more business opportunities, wider geographical scope and significant knowledge and technology exchange.

‘The merger will help us not only retain the excellent firms within our existing organisations but also attract new members who are looking for a different approach and greater support from a global international network.’

Michael Parness, president of CPAAI, added: ‘Our organisation and MGI Worldwide have a lot of shared values, a similar client base and business DNA, so this merger makes sense in a world that is becoming ever more interconnected.

‘Clients remain at the heart of all members firms’ objectives and the merger ensures that they will be able to call on the expertise and support they need, regardless of where they operate in the world.

‘We are very excited about what the future holds for our newly formed organisation and we cannot wait to start developing new strategies and connections so that we can grow and flourish in this competitive marketplace.’

The new group will be co-chaired by Roger Isaacs, chairman of MGI Worldwide and Jim Holmes, chairman of CPAAI. Clive Viegas Bennett will take over the chief executive officer role, which he already holds at MGI Worldwide, while CPAAI's Michael Parness is named as chief operating officer.

The organisation plans to hold a series of regional meetings for its members in North America, Latin America, Europe, UK and Ireland, Africa, Asia, Australasia and the Middle East, to keep them abreast of technical and business developments, exchange business and expertise, and deepen their strong regional structure.