Umno supreme council member Reezal Merican Naina Merican has lauded Johor crown prince Tunku Ismail Sultan Ibrahim as a "rational voice" and urged all Malaysians to heed his advice.

Reezal also criticised netizens who had rebutted the crown prince's lengthy commentary on Facebook yesterday.

"The rational voice of an influential person such as the Tunku Mahkota Johor should not be sidelined.

"The attitude of some netizens who criticised Tunku's heartfelt message is regretted," Reezal Merican said in a statement today.

Tunku Ismail had launched a thinly veiled attack on Pakatan Harapan chairperson Dr Mahathir Mohamad and urged Johoreans not to change a ship's engine simply because the skipper was problematic, in an apparent reference to the current political scene.

Reezal said Tunku Ismail's comment should not be construed as a form of political interference, but should instead be respected and appreciated.

He added that the Johor crown prince's view was based on his concern about the country's direction.

"The appropriate etiquette is for the people to accept Tunku Ismail's criticism and views as a guide for their political decision.

"Personally (I see) the opinion (by Tunku Ismail) as not only for Johoreans but also all Malaysians," he said.

Reezal said the effort to make Malaysia great should not be grounded in vengeance or the politics of an individual who has a "forked tongue."

Tunku Ismail in his comment piece had referred to a leader with a "forked tongue," but did not name Mahathir directly. 

"The criticism should stir the hearts of everyone. TMJ's reminder does not end at the Johor border, but is a reminder for all Malaysians," he said.

TMJ's comment came amid an attempt by Harapan, led by Mahathir, to make inroads in Johor and other key battleground states.

The Parliament was dissolved yesterday and an election must be called within 60 days.