ISTANBUL • He may be languishing in jail, but with his books flying off the shelves, Kurdish politician Selahattin Demirtas has joined an illustrious line of Turkish prison writers.

A former presidential candidate and persistent thorn in the side of Turkey's current leader Recep Tayyip Erdogan, Demirtas has spent more than three years in jail and faces up to 142 years more if convicted of ties to Kurdish militants, which he denies.

"I am engaged in a major battle of wills because I am a political prisoner and this is motivating me to expose my creativity," Demirtas said in written responses sent to Agence France-Presse through his lawyers from his cell in western Edirne city.

Despite the possible sentence hanging over him, he has found some consolation in his ever-growing number of readers as sales of his books, written in Turkish, reach into the hundreds of thousands.

His first book, Seher (Dawn), was published in 2017 - a collection of short stories that contain glimpses into daily lives of ordinary people, including women characters whose voices often go unheard.

It has turned into a runaway success, translated into 16 languages with 240,000 copies printed.

Demirtas has followed up with another short story collection Devran, and now a full novel, Leylan.

"I would without hesitation choose literature" over politics, Demirtas said.

The charismatic politician, who founded and led the Peoples' Democratic Party, was once nicknamed the "Kurdish Obama" by some admirers for his rhetorical skills.

But the 46-year-old former lawyer was detained in the sweeping crackdown that followed a failed coup in July 2016, which Mr Erdogan's critics say was used as a pretext to remove opponents and civil society activists.

"Today politics is nothing more than a collective swindle. We are jailed because my friends and I are not involved in this fraud ring," Demirtas said.

"Literature is, however, a more naive, cleaner domain," he said, where "every reader is at least free to make his own decisions".

Writing is also a form of "resistance" to the monotony of prison life, he added.

"There is nothing here but four walls and a door. We spend almost all our time in a small cell... everything is directed towards weakening the human will and wrecking one's personality."

Despite his widespread popularity, Demirtas has many detractors in Turkey's bitterly divided political scene.

Many Erdogan supporters and nationalists say he has failed to sufficiently distance himself from the Kurdistan Workers' Party, an armed group which has waged a decades-long insurgency against the state.

Demirtas's publisher, Emir Ali Turkmen, head of Dipnot publishing house, said the politician had joined a long line of famed writers working in Turkish cells.

"Unfortunately Turkey's prisons have produced many writers throughout history. Nazim Hikmet, who is famed today as one of the world's greatest poets, did some of his best work in prison," he said.

He reeled off other high-profile names, such as Orhan Kemal, Aziz Nesin and Sabahattin Ali - the latter known for his bestseller Madonna In A Fur Coat. Jailed twice in 1933 and in 1941, Ali was killed while attempting to flee the country.

"Unfortunately, that's Turkey's fate," said Mr Turkmen.

Dipnot has received threats from nationalists for publishing Demirtas, but Mr Turkmen says the pressure was not comparable to the days when books written in prison were banned by the authorities.

The controversy has certainly not been bad for sales. In a recent visit to a book shop in an upmarket neighbourhood of Istanbul, Demirtas' newest book was completely sold out.

"There is a sympathy for Demirtas and the books have offered a glimpse of hope for many segments in society. Even the hesitant now tend to buy and read them," said bookseller Burcu Yazlar.

Mr Cahit Segmen, a book reader in Ankara, said: "I bought one of his books both to know him closer and also to see his literary side. I also find him politically close to my beliefs and so I want to support him."

Demirtas says books, dreams and news from outside keep him inspired.

He remains fiercely defiant against those who have locked him up: "No matter what black propaganda and slander they hide behind, our resistance will be overpowering."

AGENCE FRANCE-PRESSE