Pioneering Italian fashion designer Nino Cerruti has died at the age of 91, according to media reports Saturday.

Cerruti, who dressed many a Hollywood star in his heyday, introduced "casual chic" into men's fashion when he created the first deconstructed jacket in the 1970s.

He died at the Vercelli hospital in the northwest region of Piedmont, where he had been admitted for a hip operation, the Italian daily Corriere della Sera reported on its website.

Cerruti was one of the leading figures in men's ready-to-wear fashion in the 20th century, with a style that was at once elegant and relaxed.

"A giant among Italian entrepreneurs has left us," said Gilberto Pichetto, deputy minister for economic development.

Tall and slim, he always insisted he be the first to try on his creations, many of which were kept at the textile factory his grandfather founded in the northern town of Biella in 1881.

"I have always dressed the same person, myself," he once said.

Born in 1930 in Biella, Cerruti dreamt of becoming a journalist.

But after his father died when he was 20, he was forced to give up his philosophy studies to take over the family textile factory.

In the 1960s, he met Giorgio Armani and hired him as a creator of men's fashion.

The duo made a profound mark on the world of fashion, before Armani branched out on his own with his own fashion house in 1975.

Cerruti opened his first shop in Paris in 1967, launching his luxury brand into global fame.

"Clothes only exist from the moment someone puts them on. I would like these clothes to continue to live, to soak up life," he said.

While French students protested in 1968, he revolutionized fashion by asking male and female models to walk down the catwalk in the same clothes.

"Trousers have given women freedom," said the designer, who in the 1970s created his first line of women's clothing.

The man nicknamed the "philosopher of clothing" dressed American actors Richard Gere and Robert Redford as well as French star Jean-Paul Belmondo.

He also made cameo appearances in Hollywood films "Cannes Man" (1996) and "Holy Man" (1998).