WPP has reported slowing sales growth in its third-quarter revenues, but continues to grow at a faster pace than rivals Publicis and Omnicom.

The advertising giant reported it was on its way to meeting the predicted sales growth of this year of more than 3%, but anticipates that it will slow down in the fourth quarter.

Reported revenues for the third quarter came in at $4.6bn.

The company, run by Sir Martin Sorrell, also said that it wants to improve its operating margin by 0.3% this year, excluding currency shifts. It also said that its margin had improved by 0.4% over the first nine months of this year.

“Whilst clients may be more confident than they were in September 2008, they broadly remain unwilling to take further risks, particularly given multiple geopolitical flash points,” WPP said in a statement.

Like-for-like net revenues – which strips out the effects of currency swings, acquisitions and disposals – had grown by 7.6%.

Sorrell added that protests in Hong Kong and the spread of Ebola were geopolitical risks.

Last week, Publicis Groupe revealed a 4.4% rise in its Q3 revenues.