Prominent political activist Alaa Abdel-Fattah is to commence a partial hunger strike after being on full hunger strike for 100 days, said his sister, rights activist Mona Seif, Wednesday.

According to Seif, her brother decided to end his full hunger strike after recent health problems related to his kidneys. 

"We spoke with him and he agreed to make his hunger strike a partial one," Seif said on her Twitter account. 

The activist is on hunger strike to protest Egypt's controversial protest law, which he was jailed for violating, as well as what he described as the maltreatment of prisoners.

Abdel-Fattah is being retried, along with 24 other defendants, in proceedings known as the Shura Council case on charges including illegal protesting, assaulting a police officer and destroying public property. 

The next session of the trial will be Thursday.