Italian designer Giorgio Armani, one of the biggest names in the world of fashion, has died at the age of 91, the company that he founded and led for five decades said on Thursday.

Armani, synonymous with modern Italian style and elegance, combined the flair of a designer with business acumen as he directed a company generating some 2.3 billion euros (US$2.7 billion) in annual turnover.

"With infinite sorrow, the Armani Group announces the passing of its creator, founder, and tireless driving force: Giorgio Armani," the fashion house said in a statement.

He had been unwell for some time and was forced to drop out of his group's shows at Milan's Men's Fashion Week in June, the first time in his career he had missed one of his catwalk events.

Armani remained the sole owner of his company and worked with a tight-knit group of long-time colleagues and members of his family.

"In this company, we have always felt like part of a family," the company said in the statement.

"We, the employees and the family members, who have always worked alongside Mr. Armani, commit to protecting what he built and to carrying his company forward in his memory, with respect, responsibility, and love," it added.

Known as "Re Giorgio" – King Giorgio in his native Italian – the designer famously oversaw every detail of his collection and all aspects of his business, from advertising to fixing models' hair as they headed out on to the runway.

A funeral chamber will be set up on Saturday and Sunday in Milan, the city he made his home, followed by a private funeral at an unspecified date, the company said. (Reuters)