Food maker Mondelez, MDLZ.O which manufactures brightly colored Sour Patch Kids and Swedish Fish candies, is actively working to switch to natural dyes for products that use synthetic colors, the company said in an email, without giving a time frame for the transition.

The Chicago-based company, which also makes Oreos and chocolate brands like Milka popular in Europe, said the work is in line with changing consumer preferences and local laws. In 2015, Mondelez said it would remove artificial colors and flavors in many of its brands by 2020.

U.S. Health Secretary Robert F. Kennedy Jr. has been pressuring food makers to ditch synthetic dyes by the end of next year. So far he and U.S. Food and Drug Commissioner Marty Makary have relied on voluntary commitments from companies rather than regulatory changes.