Imprisoned blogger Raif Badawi has launched a hunger strike over mistreatment by the Saudi prison officials, his wife Ensaf Haidar said on Twitter on Friday.

She added that officials have so far failed to respond, but "the prison director wants Raif to continue the strike!"

Former Canadian Justice Minister Irwin Cotler reported that the Saudi authorities were "intensifying their ill-treatment" of the 35-year-old Badawi.

"As part of their cruel crackdown, they've just confiscated his books & crucial medication," tweeted Cotler, who serves as head of the Montreal-based Raoul Wallenberg Center for Human Rights.

Ensaf Haidar told DW that her husband is suffering kidney problems.

Read more: From Badawi to Khashoggi: Freedom of speech in Saudi Arabia

Saudi authorities arrested Badawi on the charge of "insulting Islam" in 2012, after he criticized the kingdom's theocentric system and urged "freedom and respect" for differing ideas in his blog.

Eventually, Badawi was sentenced to 10 years in prison, 1,000 lashes, and a fine. He received his first set of 50 lashes in a public whipping in 2015. Since the beginning of his imprisonment, he has reportedly gone on hunger strike on at least two occasions.

In 2015, Badawi received DW Freedom of Speech Award.

'Seven years of prison is enough'

Badawi's wife, Ensaf Haidar, sought refuge in Canada with their three children. She continues to advocate for her husband's release.

On Friday she spoke with DW. She said, "Last week, my husband called from a public telephone in the prison to tell me that he would begin another hunger strike."

She says: "The changes he called for on his blog are becoming policy: Women can drive. The power of the religious police is being restricted. The value of cinema and theater are being acknowledged. And women are getting the right to travel without seeking approval from their legal guardians."    

Ensaf Haidar also took the opportunity to appeal to the Saudi government during her interview with DW, saying: "Seven years of prison is enough. Raif is not a criminal, he was a free man who defended his rights as a human being. Raif has three children that have not seen him for seven years. My children need their father."

In a rare rebuke to Riyadh this week, US Vice President Mike Pence urged Saudi Arabia to free Badawi, whom Pence described as a defender of religious liberty "despite unimaginable pressure."

"And the American people stand with them," Pence said. Earlier this year, Reporters Without Borders (RSF) sent a team to Saudi Arabia to lobby for Badawi's release and the freeing of 29 other incarcerated journalists.

Khalid Salameh of DW's Arabic service contributed to this report.

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