CANNES, France (AFP) - British actor Timothy Spall claimed the best actor prize at the Cannes Film Festival Saturday for his role as eccentric British painter JMW Turner in "Mr. Turner" by director Mike Leigh.

In the lush historical biopic, Spall portrays Turner, credited with blazing a trail for modern art, in a grunting, snorting, spitting, womanising warts-and-all performance that critics hailed as riveting.