The leading social network wouldn't disclose financial aspects of the alliance with Omnicom, but online reports indicated it could be worth as much as $100 million in ads from clients the agency represents.
"Omnicom shares our passion for and understanding of the mobile Instagram community," Facebook director of market operations Jim Squires said in an email reply to an AFP inquiry.
"Our teams are going to work hand in hand to develop and execute campaigns that provide people with amazing imagery and drive meaningful business results for advertisers."
Squires maintained that Instagram's advertising strategy will continue to involve displaying a limited number of high-quality images or videos from brands that already have a strong presence at Instagram.
Instagram in November began displaying ads as Facebook moved to start making money from the smartphone photo sharing service it bought in a billion-dollar deal in early 2012.
Instagram's opening roster of advertisers included Adidas, Lexus, PayPal, Burberry and Ben & Jerry's ice cream.
California-based Facebook is carefully adding magazine-quality photo ads to Instagram as it hopes to bring in revenue from the service without alienating users.
Get your daily dose of tech news, reviews, and insights, in under 80 characters on Gadgets 360 Turbo. Connect with fellow tech lovers on our Forum. Follow us on X, Facebook, WhatsApp, Threads and Google News for instant updates. Catch all the action on our YouTube channel.