Shipping accountant Moore Stephens LLP is being merged with rival BDO to create the UK's fifth-biggest accounting firm by revenue.
BDO said discussions are at an advanced stage on a deal that would make a combined entity a leader in advising the UK’s entrepreneurial mid-sized businesses.
Completion is expected in spring next year.
The merged operation would have revenue of £590m ($758m) and 5,000 staff.
