Electoral watchdog Bersih will proceed with its defamation suit against Sungai Besar Umno chief Jamal Md Yunos for alleging the NGO coalition is infiltrated by IS.

Jamal, who leads an anti-Bersih group referred to as the 'Red Shirts', also claimed he has information that Bersih would besiege Putrajaya and airports during its Nov 19 rally in Kuala Lumpur.

Bersih chairperson Maria Chin Abdullah said the defamation suit will be filed after Jamal yesterday tore up and flushed down the toilet Bersih's letter of demand for an apology and retraction.

"Yes, we will proceed with the legal action on Friday," she told Malaysiakini.

Bersih had earlier gave Jamal a 48-hour notice, which expires today, to apologise for his remarks.

Jamal, however, refused to do so and instead flushed the letter of demand down the toilet in front of journalists after calling it "filth".

He had also lodged a police report over his ‘terror and siege’ claims but Deputy Home Minister Nur Jazlan Mohamed said police should not investigate the matter.

He said there is no need to respond to Jamal's theatrics and suggested that Bersih opened the floodgates of critics when it announced its mega rally on Nov 19.

Men in red shirts, including Umno Youth exco member Armand Azha Abu Hanipah, tried to block Bersih's nationwide convoy last weekend but was stopped by police.

The Bersih 5 rally is to demand clean election, clean government, empowerment of Sabah and Sarawak, a stronger parliamentary democracy and the right to dissent.

The three-day Bersih 4 rally in August 2015 saw at least 100,000 people throng central Kuala Lumpur to demand, among others, Prime Minister Najib Abdul Razak's resignation amid corruption allegations.

Najib has repeatedly denied abusing public funds.