Health and Human Services Secretary Robert F. Kennedy Jr. told the vaccine-skeptic group Children's Health Defense on Thursday they have "a friend in the White House" in President Donald Trump.

Kennedy delivered the keynote address in Washington, D.C., at a conference hosted by the group, noting that Trump has given directives to strengthen research, transparency and parental choice around childhood vaccines.

"Let me be clear. You have a strong and steadfast friend at the White House," Kennedy said.

Kennedy also said he wanted to make more sweeping changes on "day one" but couldn't do so due to "procedures."

"In government, a bunch of things have to happen before something else happens or you get sued," he said. "It's a very laborious system and there's a lot of inertia built in that ... if we were able to overcome it we would have changed things on day one, but those would have been short-lived and I would have been out ...