Deloitte’s UK arm has sealed a ‘first of its kind’ alliance with US immigration firm Berry Appleman & Leiden (BAL), a deal that will see it acquire the law firm’s operations outside of its home country, as the Big Four accounting firms continue their push into the legal services market.

As well as the alliance, which gives BAL access to Deloitte’s scale and expertise outside of the US, Deloitte UK will acquire the law firm’s non-US business, which includes offices in eight countries including a UK base in London.