NEW YORK--Interpublic Group's PR revenues rose by 4.8 percent on an organic basis in 2012, driven by growth at Weber Shandwick, GolinHarris and DeVries.

IPG PR firms improved by 3.4 percent in the fourth quarter of 2012, on an organic basis. The CMG unit, which houses the group's PR, branding and event management operations, increased by 2.7 percent in Q4 2012, up 8.2 percent for the year.

The results come after the holding group's PR operations grew by 4.3 percent in the first half of 2012, and 5.9 percent in the third quarter of last year.

Earlier this month, Omnicom Group reported PR revenue growth of 3.3 percent for 2012. Publicis Groupe has also recently reported 2012 results, but chose not to break out numbers for its PR operations under MSLGroup.

It is understood that growth at Weber Shandwick outpaced the group's overall increase in PR revenues.

Weber Shandwick CEO Andy Polansky told the Holmes Report that the firm has seen an improvement in digital and social media, consumer, corporate and healthcare. It is understood, however, that CMG's lobbying business continues to be stymied by political deadlock in Washington DC.

Overall, IPG reported a 0.7 percent increase in revenue to $6.96bn in 2012, although fourth quarter revenue slipped marginally to $2.06bn.

Net income for the group rose to $313.3m in the fourth quarter, from $259m a year earlier.