Wren told a Merrill Lynch advertising and marketing conference in New York that as the economic climate showed signs of continued improvement, clients were changing their priorities from cost cutting to investment, which he said was seeing bigger marketing budgets.
"We're going to achieve double-digit revenue and net income growth this year," Wren told investors.
On the acquisition front Wren said that Omnicom, which owns the TBWA\, BBDO and DDB Worldwide ad networks, would not be making any huge purchases.
However he did not rule out the world's largest advertising holding company making smaller acquisitions as it looks to extend its range of services.
"You won't see us buying anything huge, no large networks. But you will see us following the strategy we followed for the last several years of extending the services that really address themselves to our top clients," he said.
The Omnicom chief said that agencies were starting to benefit as clients boost marketing spend and continue to consolidate their ad accounts.
Wren said part of the economic fillip for agencies was coming from the trend of clients to consolidate their marketing service accounts with just a few agencies.
He said this situation could put a squeeze on mid-sized advertising companies.
His comments echo those made by WPP Group chief executive Sir Martin Sorrell recently, who again picked out mid-sized Havas as being an acquisition target.
"Strategically, its [Havas] position is vulnerable. Havas has to decide where it is, given what's happened client-wise. MPG wants to be a top-five media player. It has to decide how to get there," Sir Martin said.
Wren also used the conference to endorse comments made by Procter & Gamble's marketing chief Jim Stengel, who told a conference recently that advertisers must look beyond the 30-second television spot.
"There must be, and is, life beyond the 30-second spot. But our systems still revolve around that," Stengel told the American Association of Advertising Agencies' media conference.
Wren said that the requirements for proving a return on investment for advertising were tightening and that agencies could no longer just do TV commercials.
"You can no longer just do TV commercials," he said. "The ROI requires that you seriously look at how you're going to take this brand awareness you are going to create through the sales process, through the distribution process."
According to reports analysts are predicting Omnicom's revenues will rise to $9.6bn (£5.23bn) in 2004 from $8.6bn in 2003.
Last month, Omnicom saw its quarterly profits rise by nearly 10%. The group posted a fourth-quarter net profit of $221.3m, or $1.17 a share, up from $201.5m the year before.
Overall, revenue grew to $2.5bn from $2.1bn. US revenue rose 15% to $1.3bn while international revenue increased 22% to $1.2bn.
Analysts say that Omnicom holds a more stable position than its two main competitors, Interpublic Group and WPP, ahead of an expected rise in adspend this year from the Olympic Games and the US Presidential elections.
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