RIO DE JANEIRO: Renowned Brazilian architect Oscar Niemeyer is in hospital in a serious condition.

The Samaritano Hospital in Rio de Janeiro said the 104-year-old was "lucid and breathing without the aid of machines" but had a worrying kidney problem. He was admitted on Tuesday suffering from dehydration.

The architect designed much of Brazil's futuristic capital, Brasilia, as well as helping to design the United Nations building in New York.