WPP saw its shares rise by as much as 4% in morning trading in London before dropping back slightly.
The gains followed Omnicom's investor presentation where the US ad giant said that it had increased the amount it estimates it owes for acquisitions from between $250m (£162m) and $350m to $376.5m.
Omnicom saw its shares rise by 6% after it began to fight back against allegations of dubious accounting practices. Its share price closed at $47.56 in New York last night, up by $2.87 or 6.21%, as investors reacted to its efforts to clear up the cloud surrounding its accounting practices.
WPP was not the only stock to rise in London. Cordiant was up 2.7% to 73.5p and media-buying group Aegis, which owns Carat, was up 0.28% to 90.25p.
The Interpublic Group of Companies rose 3.6% to $24.66 and Publicis Groupe was up 3.1% to $26.35. In Paris, Havas also bounced back rising 2.6% to €6.
Jeremy Lewis, a media analyst at Numis Securities, told Reuters: "There's a little bit of blue sky out there and these stocks, like WPP and Cordiant, have all had a flip-up on the back of this."
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