KUALA LUMPUR, Sept 29 ― The unilateral interpretation of Islam by the ulama class here puts Malaysia in the same class as those leading militant religious group Islamic State (IS) in the Middle East, Datuk Zaid Ibrahim said today.

An Islamic society that does not allow for different interpretations of its faith stifles constructive religious discourse and promotes extremism, the one-time de facto law minister cautioned.

"How will we be able to establish Islam as a religion of peace if we are fearful of other ideas and resort to tyranny of thought instead? Where can we hope to end up if we only subscribe to thinking that has been sanctioned by the state?" he said in his latest post on his blog, the Zaidgeist.

The former lawyer and politician urged Prime Minister Datuk Seri Najib Razak to speak with the country's Islamic scholars and other authorities to be less rigid on their interpretation of their religion.

"He must put a stop to what is happening now, which is allowing the ulamak to unilaterally define what Islam is, what is permissible under the faith and what is not.

"In fact, based on the fact that we allow Islam to be defined solely by those in power, Malaysia is no different from the IS in the Middle East," Zaid said.

He noted the prime minister's strongly-worded speech against the brand of Islam espoused by the IS at the United Nations last week had drawn high praise from world leaders, including US president Barack Obama.

"Malaysia must not be a country that is run by tyrants in Brioni suits. This makes our leaders no different from IS leaders, except for their choice of wardrobe," Zaid said in his blog, referring to a luxury brand of men's apparel.

The Kelantan-born said the alleged "tyranny" was no more apparent than in the case of Muslim intellectual Kassim Ahmad, who was charged in the Federal Territories Shariah Court for insulting Islam and defying religious authorities at a seminar officiated by former prime minister Tun Dr Mahathir Mohamad last February.

Zaid argued that the elderly scholar should not have to face punitive action just because he held a different view from the ulama class on what constitutes the primary source of Islam.

This, he said, is where the political class need to show leadership in allowing for a more open interpretation of Islam that is not bound by the words of state-sanctioned religious leaders.

"This is the tragedy of the Muslim community. Their leaders know what the problem is but they are afraid of the ulamak.

"That's why in many Muslim-majority countries, political leaders do not incur the wrath of the ulamak or the mullahs," he said.

Putrajaya has condemned the IS as a terrorist group but some Malaysians have been making their way to Syria to join in the fighting to create a religious caliphate there.

Earlier today, the Bloomberg news service reported that as many as 40 Malaysians are currently fighting for the IS in Syria, with some saying that the jihad was mandated by the Prophet Muhammad.

The violence and brutality committed by terrorist groups in Iraq and Syria poses a threat to the Middle East and, if left unchecked, the world, the 10-member Association of Southeast Asian Nations said in a statement on September 27.

On August 11 this year, Hong Kong daily South China Morning Post reported that Malaysian police have revealed local jihadists who joined IS are now training their sights on Putrajaya.

A senior Malaysian police official was reported as saying that suspected jihadists had planned attacks on entertainment venues in Kuala Lumpur and a Carlsberg factory in Petaling Jaya.