Zuckerberg didn't give a more concrete timetable while discussing the new feature with analysts in a conference call Wednesday following Facebook's latest quarterly earnings report.
The additional options will expand Facebook beyond the renowned thumbs-up symbol that people click on to show they like a comment, photo or video posted on the social network.
The new reactions will include symbols for "angry," ''sad," ''wow," ''haha" and "love."
"We want people to be able to share all of the things that are meaningful to them, not just the things that are happy and that people are going to like when they see it," Zuckerberg said Wednesday.
Facebook is hoping the additional choices will encourage people to share their thoughts more frequently and hang out on the social network for even longer periods than they already do.
Facebook has been testing the different reactions in Chile, the Philippines, Portugal, Ireland, Spain, Japan and Colombia.
Zuckerberg said Facebook's engineers still need to make a few more "tweaks" before the new options are offered in other parts of the world.