Facebook is testing a buy button for ads on its website. (Facebook) Facebook Inc is testing a new "buy" button on its website that will let consumers purchase products that are advertised on its social network.

The new service, which Facebook described on Thursday as a test with a "few small and medium-sized businesses" in the United States, represents the Internet social networking company's latest effort to play a bigger role in the e-commerce business.

Facebook said its new Buy button will be available on the mobile and desktop PC version of its website and will allow consumers to purchase goods directly from participating businesses.

"None of the credit or debit card information people share with Facebook when completing a transaction will be shared with other advertisers, and people can select whether or not they'd like to save payment information for future purchases," the company said in a blog post on Thursday.

Facebook is not currently taking any portion of the revenue for products sold with the Buy button, a source familiar with the matter told Reuters. Credit card transactions will be handled by a third-party payment processing company, the person said.

Facebook in 2012 introduced a way for its users to buy their friends gifts such as socks and teddy bears. But Facebook stopped selling physical goods through the service after a year, letting consumers buy only gift cards instead.