The company, which has wooed new customers by promising targeted campaigns based on large pools of data, said its business model would prove to be more resilient than that of bigger rivals WPP and Omnicom. Publicis's quarterly underlying sales fell by 13% to 2.29 billion euros (2.08 billion pounds), above the average of 18 analyst estimates compiled by the company, which predicted a fall of 20% over the period.

The key metric benefited from the addition of large new customers in 2019 such as Walt Disney Co, Bank of America and Novartis.

These new accounts helped limit revenue losses in North America, the company's number one region in terms of sales, as brands scaled back their spending.

The Paris-based company said second-quarter underlying sales in North America fell by 7.6%, just a third the fall seen in Europe, where countries such as France, Spain and Italy imposed very strict national lockdowns.

Looking ahead, Publicis said the uncertainties caused by the coronavirus pandemic prevented it from providing any full-year guidance, although it predicts operating margins will be higher in the second half of the year than in the first half.

The group added it had already cut 286 million euros in costs out of the 500 million it hastily planned in April for 2020 and that it could further "adapt its cost base" as needed.

"If the health situation deteriorates and there's an additional impact on the economy, we'll be able to expand this (cost-cutting) plan," chief executive Arthur Sadoun said in a call with reporters.

By Mathieu Rosemain