Andy Kaufman's brother has fueled the mystery surrounding the comedian's death by claiming the funnyman is still alive and even fathered a daughter after he is said to have lost his battle with lung cancer.

The Taxi star passed away at the age of 35 in 1984, but fans have long speculated that his death was a hoax.

Rumours about Kaufman's fate resurfaced on Monday after his brother Michael gave a bizarre speech during the annual Andy Kaufman Awards in New York City.

Michael told the audience that he believes the funnyman faked his own death, and alleged that he discovered an essay written by Andy which included details on how he planned to pull it off.

He also claimed the letter instructed him to go to a specific restaurant on Christmas Eve, 1999, upon which an anonymous man handed him another missive, which he read aloud to the New York City crowd.

Andy allegedly wrote "everything was great in his life and he just wanted to get away from being Andy Kaufman," adding that he had fallen in love with a woman and the couple were raising a daughter together.

At that point, Michael shocked the audience by bringing a young woman onto stage and introduced her as the 24-year-old daughter Andy spoke of in the letter.

In video footage taken at Monday's event, obtained by TMZ, the unnamed woman backed Michael's story and claimed Andy has been living in secret as a stay-at-home dad.

She also claimed that Andy originally agreed to come out of hiding after 29 years to attend the awards, but backed out at the last minute.

The Hollywood Reporter has since contacted Michael, who claimed the mystery woman was impossible to reach for further questions.

If Kaufman was still alive today, he would be 64 years old.