Brazilian architect Oscar Niemeyer, hospitalized at a medical center since early this month, has suffered a deterioration of his kidney function, medical authorities said Saturday.

The celebrated 104-year-old architect, who was admitted to Rio de Janeiro's Samaritano Hospital on Nov. 2, is lucid and receiving respiratory physiotherapy according to the latest medical bulletin, which offered no further details about Niemeyer's renal problem.

According to the director of the medical center, Fernando Gjorup, who signed the bulletin, at present there is no plan for Niemeyer's release, since his condition requires medical attention.

Doctors monitoring the architect's health said Friday that the patient had suffered a digestive hemorrhage, which, however, was under control - one more complication on top of his kidney problems.

Niemeyer spent two weeks in hospital in October and was then released, but was soon readmitted due to a relapse.

His wife, Vera Lucia Cabreira Niemeyer, said when he was hospitalized for the second time that the centenarian architect was working on several projects, among which she mentioned a cultural center in Morocco and a library in Algiers.

His family has faith that Niemeyer will be able to celebrate his 105th birthday at home on Dec. 15.

A disciple of Switzerland's Charles Edouard Jeanneret-Gris, known as Le Corbusier, Niemeyer has been one of the leading exponents of architectural modernism and created the principal government buildings of Brasilia, the capital city he designed together with architect and urban planner Lucio Costa. EFE