The Wall Street Journal reported that Kevin Systrom and Mike Krieger had decided to exit after verbal jousts with Facebook executives over the extent of Instagram's autonomy.

Growth tactics and methods of expanding the user base were some of the things that the debates had covered, a source said, while another source indicated that Systrom and Krieger had not been happy working within a large company.

“We’re planning on taking some time off to explore our curiosity and creativity again,” Systrom and Krieger said in a statement. “Building new things requires that we step back, understand what inspires us and match that with what the world needs; that’s what we plan to do.”

In June, the founders of WhatsApp, Jan Koum and Brian Acton, quit Facebook over disagreements with the social media giant about advertising on the encrypted messaging app. Facebook bought WhatsApp for US$22 billion in 2014.

In a statement, Facebook founder Mark Zuckerberg said: “Kevin and Mike are extraordinary product leaders and Instagram reflects their combined creative talents

“I’ve learned a lot working with them for the past six years and have really enjoyed it. I wish them all the best and I’m looking forward to seeing what they build next.”

The WSJ report said current and former employees were surprised by the two men's moves which had not been announced within the company.

Systrom and Krieger are regarded as key defenders of Instagram’s culture within Facebook and respected among Instagram employees.

While Facebook's disputes with Koum and Acton revolved around advertising, Instagram embraced advertising very early on.

The WSJ quoted people familiar with the situation as saying Facebook and Instagram executives had begun to argue over Instagram's independence within the social media company.

Instagram had more than a billion monthly active users this year, adding hundreds of millions of users in about 18 months.

When Facebook's value plunged sharply in July, the importance of Instagram was reinforced, with popularity among younger users seen as key to user growth.

The report said one of bids to grow Instagram’s popularity was a June launch of a new hub for long-form video, called IGTV. This marked Facebook’s latest bid to tap into growing demand for video on mobile devices.