PKR de facto leader Anwar Ibrahim has defended the flash mob which ridiculed Prime Minister Najib Razak over his use of 'kangkung' (water spinach) to explain the issue of price hikes.

The hilarious event , organised by Machang Bubuk assemblyperson Lee Khai Loon, was held in a night market area in Alma, Bukit Mertajam on Wednesday.

Anwar said Umno Youth and Malay rights group Perkasa have been insulting Pakatan Rakyat leaders but few had protested.

He argued that the butt dance by pro-government groups comprising army veterans in front of former Bersih coordinator Ambiga Sreenevasan in 2012 was much worse than the ‘kangkung’ flash mob.

"How come there was no protest when the butt dance happened? Is the act right from the aspect of religion or (moral) behaviour?" asked the Permatang Pauh MP, when met during his trip to Sungai Lembu yesterday.

"You cannot defend that (butt dance) compared to what (Lee) Khai Loon did," Anwar said.

On Wednesday, about 15 people joined the flash mob to protest against growing inflation, where bundles of the green leafy kangkung was stuffed into the gaping mouth of a replica of Najib made from styrofoam.

Umno leaders have bandied together to condemn Lee for being "rude, childish, having low mentality, and conduct unbecoming of an assemblyman" for ridiculing the country's number one leader, demanding an apology for his actions.

Pulau Betong assemblyperson Muhammad Farid Saad had asked Chief Minister Lim Guan Eng and Pakatan leaders to take Lee to task over his ill-mannered behaviour.

Farid had backed Najib, saying his speech was taken out of context when he only meant that while there were prices of essential goods which have gone up, others had decreased, such as kangkung.

Najib has since clarified his much lampooned remark, explaning that he had used the vegetable as an example of how market forces determine food prices.

Feeling the pinch

According to Anwar, the prime minister was ridiculed by the whole country and not only by Lee, a first-time assemblyperson - he won the Machang Bubuk state seat in a six-cornered fight last year.

The opposition leader added that Najib had unfortunately made the statement in Kemaman, Terengganu about the prices of kangkung at a time when Malaysians are feeling the pinch of price hikes.

"They can say people are wrong to ridicule him as he meant something else when he used kangkung as an example in his speech," Anwar said.

"But how can you defend yourselves against the economists? That is why even the British Broadcasting Corporation (BBC) published a story about it," Anwar added.

When told that Umno was angry at the manner in which the kangkung was stuffed into Najib's replica, Anwar jested: "Okay lah , I will tell him (Lee) not to do it again."

Anwar said he too felt it was hilarious when he heard about Najib's statement, which was widely circulated through YouTube, Facebook and Twitter.

He had wanted to tweet about it but was advised to let others do it, "so I stopped myself", he said.

"But I remember Saloma's song ‘Lenggang-lenggang kangkung’..." he said, subsequently breaking into the song.

"Kangkung di tepi paya, nasib tak beruntung, dapat isteri...," he sang, but then stopped abruptly.

Everyone laughed while Anwar, apparently poking fun at Najib's wife, Rosmah Mansor, quickly added, "It's an old song."