Facebook and Instagram have banned private gun sales weeks after U.S. President Barack Obama announced new executive actions including requiring gun sellers who use the Internet to get licences and conduct background checks.

"Over the last two years, more and more people have been using Facebook to discover products and to buy and sell things to one another," said Monika Bickert, Facebook's head of product policy, in a statement released on Friday. "We are continuing to develop, test and launch new products to make this experience even better for people and are updating our regulated-goods policies to reflect this evolution."

Facebook said it would rely on its users numbering about 1.6 billion to report violations of the new policy and would remove any post related to it. It could also ban users or limit the ways they post on Facebook.

The White House said, "A person can be engaged in the business of dealing in firearms regardless of the location in which firearm transactions are conducted" including the Internet, adding that "there is no specific threshold number of firearms purchased or sold that triggers the licensure requirement."

According to the New York Times, Facebook has become the forum for gun sales without people having to undergo background checks.

The new Facebook policy covers only private person-to-person sales and not licenced gun dealers.

Obama's executive actions redefined gun dealer to include anyone who sells even a single firearm yearly, WND reported.

"The goal is keeping bad actors away from firearms," Attorney General Loretta Lynch said. "These rules will provide clear notice to those individuals who try to hide behind the hobby exception when they are selling for a profit or for a business."

Speaker Paul Ryan described Obama's action as "a form of intimidation that undermines liberty."

"He knows full well that the law already says that people who make their living selling firearms must be licenced, regardless of venue," Ryan said. "Still, rather than focus on criminals and terrorists, he goes after the most law-abiding of citizens."