Indonesian cleric Abu Bakar Bashir, right, gestures during a court appearance in 2016.
Jakarta, Indonesia CNN  — 

Abu Bakar Bashir, a radical Islamic cleric and the alleged mastermind behind the 2002 Bali bombings, has been granted early release from jail on humanitarian grounds.

Bashir, now 81, was sentenced to 15 years’ imprisonment by an Indonesian court in 2011 for inciting and financing terrorism due to his suspected ties to a militant training camp in the country’s Aceh province.

Known for his inflammatory rhetoric, he has also been accused of being the spiritual leader of Indonesia’s homegrown terror network, Jemaah Islamiyah, and is said to have inspired many of those involved in the 2002 Bali bombings and the 2003 J.W. Marriott bomb attack in Jakarta. He is also known to have pledged allegiance to ISIS during his time in prison.

On Friday, Indonesian President Joko Widodo agreed to release Bashir due to his ill health, according to Yusril Ihza Mahendra, a legal adviser to the head of state.

“The law states that parole is available once two-thirds of a sentence has been served. The most important factor was the humanitarian concern, he is an old man and not really healthy. He has also maintained very good attitude while in prison,” Yusril told CNN by phone on Friday.

Yusril said he understands that some countries will question the decision, but added that Indonesia is an independent country with its own laws.

“We have an experience on handling terrorism problems, we have a good law on terrorism, so that gives us a lot of lessons on handling terrorism problems,” Yusril explained.

Indonesia has invested heavily in counterterrorism, establishing the elite special forces unit Detachment 88, which has received support and training from the US and Australia, and has been credited with greatly reducing the number of attacks.

The decision from Widodo – who is seeking re-election in April – is likely to be controversial, given that the Australian government considers Bashir the mastermind of the 2002 bombings in Bali that killed 202 people, including 88 Australians.

Presidential candidate and incumbent President Joko Widodo, pictured left, and his running mate, Maruf Amin, during a live nationwide TV debate in Jakarta on January 17.

In the past, Indonesian authorities have tried unsuccessfully to directly link Bashir to major terror attacks in the country.

In the first two trials, prosecutors attempted to link the fiery cleric to the 2002 and 2003 blasts. The courts found him guilty of relatively minor charges and he was released after serving 25 months in jail.

Bashir has repeatedly denied all terrorism charges leveled against him and blamed a US government-backed conspiracy to keep him behind bars.

Bashir’s son, Abdul Rohim, expressed relief Friday at the prospect of his father’s parole.

“We thank you to Allah for this blessing. My father now is 81 years old and he is innocent so he deserves to be released from the prison,” Rohim told CNN.

“My father is not now really healthy, he can’t walk because of a leg problem.”

Bashir’s release will be delayed by administrative procedures but he is expected to be home as early as Tuesday, Rohim added.

Journalist Masrur Jamaluddin reported from Jakarta, with CNN’s Angus Watson and Ben Westcott contributing from Hong Kong. Lauren Said-Moorhouse wrote from London.