He said he had made jesting references to Rosmah and fashion house Jakel Trading, made during an anti-GST rally last week. “I will see them in court. I won’t apologise because I said it in jest,” he was quoted as telling Malaysiakini.

Rafizi questioned if the Prime Minister, Najib Razak, had misused funds from the Goods and Services Tax to pay for the purchase of textiles.

He said today that a defamation suit by Najib would be “overkill”, he said. “In ceramah, things are always said in jest. What I said pales in comparison to what Dr Mahathir (Mohamad) had said,” he said.

Dr Mahathir, the former premier, has made scathing remarks about Najib and the government investment company 1Malaysia Development Bhd in the course of a year-long campaign out force Najib out of office.

Rafizi said Najib should not play double standards. “If you want to be so sensitive, sue Mahathir, the Wall Street Journal and anyone who said the same thing,” he said.

He said politicians should not be too quick to resort to filing suits. “People talk about you every day…being under public scrutiny, it’s part and parcel of what public officials are,” he said.

Earlier this week, Najib’s lawyer Mohd Hafarizam Harun said he had received instructions to issue a letter of demand to Rafizi and KiniTV, which published a video of Rafizi’s remarks.

Najib has previously filed suits against Malaysiakini, Petaling Jaya Utara MP Tony Pua, Taiping MP Nga Kor Ming, the PAS party organ Harakah, former MCA president Dr Ling Liong Sik, and Rafizi himself for remarks about petrol subsidies.