The companies said the waiting period under US anti-trust laws had expired without US authorities challenging their USD 35.8 billion merger announced on July 28.
Paris-based Publicis and Omnicom of the US said the merger, aimed at boosting their ability to meet the demands of the digital revolution, has to date been approved by regulatory authorities in Canada, India, Turkey, South Africa and South Korea.
"The expiration of the HSR review period in the U.S. And the approvals received in other jurisdictions satisfy some of the conditions necessary for the transaction to close," the companies said in a statement.
The merged company, the Publicis Omnicom Group, will have a combined workforce of more than 130,000.