Carlos Fuentes, who died Tuesday aged 83, was one of the Spanish-speaking world's best known writers, famous for his prolific output and his use of experimental language.

President Felipe Calderon announced the writer's death in a message on his Twitter account. Local media said Fuentes had died in a hospital in the south of the Mexican capital as a result of heart problems.

Arguably Mexico's best known living writer, Fuentes was born in Panama on November 11, 1928, the son of a diplomat. He spent parts of his childhood in Quito, Montevideo and Rio de Janeiro and his travels helped shape his leftist political views that fueled a lifelong activism.

"You have to take some time out to be able to give literature the attention it deserves - for journalism, for speaking, for friendship. I cannot be cloistered like a monk because I would lose contact with human beings, with life," the versatile Fuentes said in a 2003 interview.

A leading figure in the 1960s Latin American boom in Spanish-language literature, Fuentes befriended both Colombian leftist Gabriel Garcia Marquez and Peruvian conservative Mario Vargas Llosa, and was known for criticizing both the harsh side of capitalism and the tough realities of communism.

Unlike his contemporaries though, Fuentes never won a Nobel Prize in literature, although for years he was mentioned as being on the short list and collected a clutch of other prestigious awards.

His travels helped shape his leftist political views and fueled his passion for political activism.

Like many Latin American intellectuals of his era, he was fascinated by the Cuban revolution for years and by leftist rebel movements; but over time his opinions grew more nuanced.

"Cuba is worthy of condemnation, and so is the United States," he was quoted as saying.

Fuentes published his first collection of short stories, Masked Days, under the guidance of his father Rafael.

At the age of 30 he achieved international renown with his 1958 book The Most Transparent Region, a portrayal of Mexico City which was experiencing explosive growth.

At the time, Mexico City was, in literary terms, "just an orange falling off a tree... all I did was eat it," Fuentes said in 2003.

He followed up with Good Consciences (1959), Aura (1962) and then The Death of Artemio Cruz (1967), which won both critical and public acclaim and became his best known work.

His Sacred Zone (1967), Hydra Head and Burnt Water were followed by essays about Spanish and Latin American literature, and Fuentes' views of the May 1968 student strikes and related events in Paris.

On the linguistic front, Fuentes also aimed to be on the cutting edge.

It is imperative "to break the mold of this dusty old heavy academic Spanish and give it new life, slap it in the face, inject some semen into it," a provocative Fuentes wrote.

Taking a turn as a diplomat, in his father's footsteps, Fuentes agreed to be Mexico's ambassador to Paris in the early 1970s.

Not long afterwards he scored a new literary success with Terra Nostra, a novel on the complex cultural issues of the Iberian and Latin American worlds for which he was awarded the prestigious Romulo Gallegos prize in 1982.

Other leading prizes were not far behind from the Cervantes (1987), to the Ruben Dario and Prince of Asturias (1994).

Fuentes's 1987 Cristobal Nonato examined the then-upcoming 500th anniversary in 1992 of the arrival of the Spanish in the Americas.

His intellectual curiosity led him down other paths to the 2002 This I Believe, on his personal ideological and literary beliefs.

In 2003 The Eagle's Chair imagined the outlines of Mexico's future, and the following year he published Against Bush - casting his ballot against the US president's reelection that year.

Fuentes supported the election of conservative President Vicente Fox in 2000, which ended the seven-decade rule of the Institutional Revolutionary Party (PRI).

"In the Americas we sometimes don't realize democracy takes a long time to cook, maybe because we are used to abrupt decisions and heavy blows typical of dictatorships," he said in 2001.

The globe-trotting Fuentes, who was married to journalist Silvia Lemus, once said his real home was an airplane and his worst fear - death.