Company has reported 17.1% increase in net revenue but 2.9% fall in organic growth.
Company will introduce reduced hours, furloughing and some job cuts this week.
A number of ad agencies have already made layoffs due to COVID-19 impact.
Publicis CEO stresses that priority is protecting health of staff.
'The last 12 months have been a tough fight for transformation, but without a doubt a necessary one,' holding company chief said.
'I didn't dare to ask for any additional help,' CEO says.
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