In coming weeks, Facebook will begin testing a shopping tab for its mobile app

Facebook said Monday that it will begin testing a shopping tab for its mobile app as it works to ramp up advertising and online commerce offerings.

Mobile advertising accounts for some three-quarters of the leading social network's revenue, and it is out to make even more money by weaving the ability to buy items more tightly with marketing messages.

"On Facebook, we've seen that people are coming to our platform not only to connect with friends and family but also with products and brands," the Silicon Valley-based Internet firm said in an online post.

"We want to build native experiences that make it easier for both people to discover products on mobile and businesses to drive more sales."

Facebook introduced a new ad format that lets people smoothly complete purchases inside the social network instead of being taken to outside websites that could stall or delay the process.

In coming weeks, Facebook will begin testing a Shop section where people can "discover, share, and purchase" products that they may currently seek out in various locations such as News Feed or Pages at the social network.

A small number of US partners will take part in the Shop section test, with an eye to expanding offerings if the results are promising.

Some new products, such as Carousel, which allows marketers to display assortments of and links in a single ad, have been previously launched.

Facebook has also introduced "Buy" buttons to streamline purchases at the social network.