The firms announced in January that Deloitte is to acquire the 285-year-old property advisor Drivers Jonas, with no capital changing hands – and no job losses. DJ is to move its 670 partners to Deloitte's much smaller real estate team by March, and its Managing Partner Nick Shepherd will assume the same role in the enlarged real estate group. The merged group will trade as Drivers Jonas Deloitte, and will have around 700 staff, annual revenues of more than £110 million. In France, the president of the Drivers Jonas unit, Chris Armon-Jones, will retain his position, the firm said.

"This is a very exciting transaction, which will truly differentiate us in this sector," said Deloitte CEO John Connolly. Added Shepherd: "The wider Deloitte business gives unparalleled access to international investors, property companies, sovereign wealth funds and high net worth individuals, who play such a key role in the operation of the capital markets. We see huge opportunity in combining Deloitte's real estate skills and wider business expertise with our full range of property and construction services."

The merger is particularly important in the UK market, boosting the combined firms' position in public sector work. Deloitte counts British Land, Hammerson and Segro among its audit clients. Connolly pointed to significant growth opportunities in the £2 billion UK real estate advisory market. Drivers Jonas, which advises on transactional work such as property lettings and investment, will bolster Deloitte's ability to execute business, while its consultancy business is "significant and complementary," he said.

Deloitte is the second-largest of the Big Four in the UK after PricewaterhouseCoopers, with 12,000 staff, 670 partners and revenues of almost £2bn - compared with £2.25 billion at PwC. The firm has trebled in size since Connolly took over in 1999, noted The Times newspaper, leapfrogging rivals KPMG and Ernst & Young. It was the only one of the four not to sell its consulting business in the aftermath of the 2002 Enron scandal which brought down Arthur Andersen. Drivers Jonas made a profit of £20 million for the year to last May on turnover of £96 million. Outside the UK, it has offices, in Paris and Frankfurt in Europe.