Legendary French fashion designer Yves Saint Laurent has died at the age of 71.

His long-time companion, Pierre Berge, said the designer had been diagnosed with a brain tumour last year and had died on Sunday in Paris.

Berge said: "Chanel gave women freedom. Yves Saint Laurent gave them power. (But) he was someone who was very shy and introverted, who had only very few friends and hid himself from the world."

Saint Laurent was acknowledged as one of the greatest style leaders of the 20th century and credited with revolutionising the way women dressed.

He was widely considered to be one of an elite club of designers including Christian Dior and Coco Chanel who made Paris the fashion capital of the world.

From Princess Grace of Monaco to the actress Catherine Deneuve, Saint Laurent's creations adorned many famous women but he was also the first designer to make luxury labels accessible to a wider audience through innovative read-to-wear collections.

He exploded on to the world stage at just 21 and built up a clothes, perfumes and accessories empire that resulted in a 1989 stock market flotation - the first by a fashion house.

But Saint Laurent was plagued by health problems suffering from severe depression and undergoing treatment for alcohol abuse.

Insiders said Saint Laurent, who never read newspapers or listened to the radio, became increasingly cut off from reality and lost touch with all but a tiny group of friends.

He was rarely seen in public after his retirement 2002 but was awarded one of France's top honours in 2007.

A memorial mass will be held on Friday in the church Saint Roch in Paris, the traditional church of artists and musicians.

The eldest child of a wealthy French industrialist, Saint Laurent was born and grew up in the then French colony of Algeria and showed a talent for design, making clothes for his younger sisters' dolls.

At 17 he entered a Paris fashion school, and his sketch for a cocktail dress won first prize in an annual contest.

Introduced to Christian Dior, he was hired on the spot by the creator of the "New Look" and became his chief assistant. On Dior's death in 1957, Saint Laurent became chief designer and swiftly outshone his mentor.

After his first collection introduced the widely copied "trapeze" silhouette with narrow shoulders and flared skirt, the shy 21-year-old was pushed out on to the Dior building balcony and crowds in the avenue below hailed him like royalty.

Saint Laurent directed Dior for three years, until drafted for military service during the Algerian war. He found army life an ordeal and had a nervous breakdown, spending nearly three months in hospital.

After Berge arranged financial backing, Saint Laurent presented his first collection under his own name in 1962.

The "YSL" empire grew steadily and Saint Laurent showed an instinctive ability to sense what the mood on the streets was and turn it into high fashion.

But by the late 1980s his health problems were an issue.

"Fame has destroyed him," Berge once said.

Despite the personal demons, his business empire thrived. The flotation of the business in 1989 flotation was a success although Berge and Saint Laurent sank into debt when the Gulf War erupted and the world economy slumped in the early 1990s.

In 1992, YSL was absorbed by cosmetics and drugs company Sanofi, with Saint Laurent retaining creative control. In 1999, it was bought by the Gucci group, itself controlled by French luxury giant PPR.

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