Hank Williams should be played by an American actor, not Tom Hiddleston, his grandson has reportedly said.

Hank Williams III claimed that Matthew McConaughey should have been cast as the late US country crooner in the upcoming biopic, rather than the Thor star.

The 41-year-old singer, who's also known as Hank 3, said that producers should have cast the Texas-born star because Matthew "represents the South, both in movies and real life" and singled out his Oscar-winning performance in The Dallas Buyers Club to prove that the actor has the right acting chops for the role.

British actor Tom, who has shared a picture of himself in character on Twitter, will show off his singing and guitar skills as Hank in a film about his life called I Saw The Light.

Marc Abraham wrote the script and will direct the film about Hank's rise to fame and life, which is based on a biography by Colin Escott.

Hank - known for hits like Your Cheatin' Heart and Hey Good Lookin' - was considered to be one of the most important country music singer-songwriters. He died from heart failure in 1953 at the age of 29.

Shooting on I Saw The Light is due to start in Louisiana later this year.