Jason Segel has revealed how he was rejected by Hillary Clinton.

The funnyman has previously joked that the former First Lady is the mystery matriarch on his show How I Met Your Mother, and after hearing his repeated references to her, Hillary wrote Jason a hilarious note turning town the chance to appear on screen with him.

"'Everyone always asks me, like on a red carpet or wherever, 'Who is the mother?' I always say Hillary Clinton as a joke. I got a letter in the mail. I got a rejection letter from Hillary Clinton," he said on Late Night with Jimmy Fallon.

On Monday, website Politico obtained a copy of the hilarious rejection letter which references a number of Jason's movies including Forgetting Sarah Marshall and The Muppets.

"I was delighted to read about your interest in sharing the big screen with me. As you can imagine, I am a little occupied at the moment, but perhaps someday I can help you forget Sarah Marshall ... again. My only condition is that there be Muppets involved, and that is non-negotiable. In the meantime, you have my best wishes for continued success with your career," the Secretary of State wrote.