Former Portuguese President Mario Soares died at the age of 92, two weeks after he was admitted to a hospital in Lisbon.

Soares on Saturday died of respiratory complications that left him in a profound coma at Red Cross hospital in Lisbon since December 13 last year, Xinhua news agency reported.

Sores was widely known in Portugal as one of the founding fathers of the country's democracy after a bloodless coup on Apirl 25, 1974, when the dictatorship of Oliveira Salazar was overthrown.

He served as president from 1986 to 1996 and prime minister from 1976 to 1978 and from 1983 to 1985. 

He also served as foreign minister and an MP of the European Parliament. When he served as minister of foreign affairs he negotiated the Portuguese entry in what is today the European Union.

Born in December 7, 1924, in Lisbon, Soares was a law graduate at Lison University and later became a lawyer. He was one of the founders and the first leader of the currently ruling Socialist Party headed by Prime Minister Antonio Costa.

Prime Minister António Costa has declared a three-day national mourning from Monday for Soares.

"Today we lost the one who was so often the face and the voice of our freedom. Mario Soares was a man who throughout his life fought for freedom, he did it against the dictatorship, suffering prison, deportation and exile," Costa said.

"The loss of Mario Soares is the loss of someone who would have been irreplaceable in our recent history. We owe him a lot and we will remain forever eternally grateful," he added.

A state funeral for Soares will be held in Lisbon on Tuesday. Costa, who is on an official visit to India, will be absent from the funeral, but he has sent his condolence to Soares' family.