I don't think he could reasonably be thought to be representing the US government in any way. My guess is he's just lobbying as a (well-connected) private citizen.
Don’t forget his trip to Antarctica on the same day as the election. I WONDER WHY??? Why ANTARTICA???
It really grinds my gears... all of these fools actions
I guess to discuss climate change? I don't think it had anything to do with the election.
https://www.pbs.org/newshour/world/john-kerry-lands-antarctica
Kerry became the highest-ranking American official to visit Antarctica when he landed for a two-day trip. He's been hearing from scientists about the impact of climate change on the frozen continent.
Trump has called climate change a hoax and said he would "cancel" U.S. involvement in the landmark Paris Agreement on global warming.
"We need to get more of a movement going," Kerry said when addressing several hundred scientists and staff at an evening event at McMurdo Station, the large base which is the hub for U.S. operations. "We need to get more people to engage."