Facebook-owned WhatsApp said Thursday it would introduce disappearing messages on WhatsApp, a move ramping up its challenge to rival Snapchat.

The messaging service used by more than two billion people globally said it would enable people to choose whether to keep their messages or allow them to delete themselves after seven days.

"Today, WhatsApp messages often live on our phones forever. While it’s great to hold onto memories from friends and family, most of what we send doesn’t need to be everlasting," a WhatsApp blog post said.

"Our goal is make conversations on WhatsApp feel as close to in-person as possible, which means they shouldn't have to stick around forever. That’s why we’re excited to introduce the option to use disappearing messages on WhatsApp."

Facebook previously introduced a similar option for its Messenger platform, following on the heels of Snapchat, which has amassed a strong following among young smartphone users.

WhatsApp chose a seven-day window "because we think it offers peace of mind that conversations aren’t permanent, while remaining practical so you don’t forget what you were chatting about," the blog post said.

"The shopping list or store address you received a few days ago will be there while you need it, and then disappear after you don’t."

The move comes with Facebook's core social network losing ground to younger audiences to rivals like Snapchat and TikTok, even as Facebook-owned Instagram continues to grow in that demographic group.

A Piper Jaffay survey of US teens last month showed Snapchat is their favorite social media platform, and that TikTok overtook Instagram for second place.