Hank Williams' grandson has reportedly criticised movie bosses for casting British actor Tom Hiddleston as the music legend in an upcoming biopic.

The late star's grandson, Hank Williams Iii, disapproves of the decision to cast a Brit in the role, and insists an American actor would have been a better choice to play the country performer, according to Tmz.com.

Williams reportedly told the website his first choice for the coveted part would be Oscar winner Matthew MCConaughey.

Hiddleston plays Williams in I Saw The Light, which will chronicle the singer's meteoric rise to fame and his untimely death at the age of 29.