Brazilian architect Oscar Niemeyer, who designed much of the country's futuristic capital Brasilia, died Wednesday, his doctors said. He was 104.

Brazilian architect Oscar Niemeyer (L), pictured here during a celebration of his 104th birthday in 2011, died at 104, his doctors said.

A spokesperson for Rio's Samaritano hospital said that Niemeyer died at 9:50 pm (1250 GMT). He was hospitalized for kidney failure a month ago and had been receiving treatment in the coronary unit.

A pioneer in the use of reinforced concrete to produce soaring, curvaceous forms, Niemeyer has designed 600 works around the world and has some 20 other projects underway.

The Brazilian icon, who won architecture's top award the Pritzker Prize in 1988, started his career in the 1930s and went on working well into the 21st century, after turning 100.

"I am not attracted by the angles or the hard and inflexible straight lines created by man," Niemeyer once told the Spanish newspaper ABC.

"What attracts me is the free and sensual curve, the curve which I find in the mountains of my country, in the flow of its rivers, in the waves of the ocean, in the body of a woman."

Niemeyer works can be found in countries as far-flung as Algeria, Italy, Israel, the United States and Cuba, whose leader Fidel Castro was one of his personal friends.

In the 1940s, he worked on the headquarters in New York of the recently-created United Nations, an initiative which symbolized hopes for a new era of peace after the carnage of World War II.

On that and other early projects, Niemeyer teamed up with another pioneer of post-war buildings in concrete, the French-Swiss architect Charles-Edouard Jeanneret-Gris, better known by his pseudonym of Le Corbusier.

In 1956, Niemeyer was appointed chief architect on the project to provide Brazil with a modern new capital city in the heart of the Amazon basin jungle -- an achievement that was to make him one of the world's best-known architects.

One of his most spectacular works was a contemporary art museum created in 1996 -- when Niemeyer was already 89 years old. Located in Niteroi, a town near Rio, it includes an upturned dish shape poised over the ocean on rocky cliffs.

The architect, who died just shy of what would have been his 105th birthday on December 15, was hospitalized on November 2 suffering from dehydration after coming down with the flu. It was the latest in a series of lengthening hospital stays.

His only daughter, Anna Maria Niemeyer, died of emphysema in June at age 82.

Source: AFP