Facebook is making major changes to its advertising strategy, including putting ads before videos and requiring videos to be longer before they can have ad breaks.

The company announced in a blog post on Thursday that it would be adding six-second pre-roll ads before videos starting next year. The ads would likely be before Watch content, Facebook's TV-style show content.

"While pre-roll ads don't work well in News Feed, we think they will work well in Watch because it's a place where people visit and come back to with the intention to watch videos," Facebook product management director Maria Angelidou-Smith and product manager Abhishek Bapna wrote in the post.

Facebook will also require videos that want to include ad breaks to be at least three minutes long starting in January, with the first ad appearing at the one minute mark. Previously videos had to be a minimum of 90 seconds, and the first ad break was allowed to appear after 20 seconds. Facebook research showed user satisfaction increased 18 percent when the ad break was later in the video, which it believes will lead to more people continuing to watch after the commercial.

The company will only allow live video ad breaks on pages with more than 50,000 followers, removing ads from people who post live videos on their profile.

"Live video publishers below this threshold also tend to have smaller audiences for their broadcasts, and therefore aren't able to garner meaningful revenue from Ad Breaks," Angelidou-Smith and Bapna wrote. "We'll continue to work jointly with our partners on testing and improving the product to deliver value."

In addition, the company said it would be rolling out changes to the News Feed to include more videos from publishers and creators that users frequently view. Creators will also be able to share their videos with all their followers.

Sponsored videos will still also be allowed. The number of branded videos has quadrupled since the beginning of 2017, the company said.