At the same time, the group, owner of the DDB, BBDO and TBWA\Worldwide networks, announced a 7 per cent jump in its fourth-quarter earnings to £152 million.
John Wren, the Omnicom chairman, said the company had won £3.3 billion in new business last year. He pledged to build on this by expanding its customer relationship marketing and internet services, as well as its Asian operations. Omnicom already plans to change its networks into mini holding companies.
Revenues for the year climbed 8 per cent to £6.2 billion with returns from the group's US domestic market double those from elsewhere.
US revenues rose 10 per cent to £3.4 billion, compared with a 5 per cent increase internationally to £2.8 billion.
Quarterly figures reflected those for the year, with US operations delivering a 9 per cent rise in revenue to almost £1 billion.
This compared with a 1 per cent rise in the rest of the world to £783 million.