The call by the Sultan of Johor for a restoration of royal powers removed over two decades ago is the latest in a spate of activism by Malaysia's nine royal houses - but this is perhaps the most significant.

Legal immunity and the right to veto legislation were stripped from the hereditary Malay rulers under Tun Dr Mahathir Mohamad, the last prime minister to wield virtually unfettered political power.

The monarchs have had renewed vigour since Malaysia's ruling Barisan Nasional (BN) coalition lost its two-thirds supermajority in Parliament in 2008 and ceded several state governments.

So far, the sultans have limited their newfound influence to flexing their muscles in the selection of chief ministers in their respective states, and making pointed statements about how the government is being run.

The most controversial was probably the joint expression of dissatisfaction from them over how investigations have been carried out into 1Malaysia Development Berhad, whose financial troubles have been linked to graft allegations against Prime Minister Najib Razak.

But the call by Johor Sultan Ibrahim Ismail to bring back royal vetoes and immunity could be a bridge too far for most Malaysians.

It was alleged incidents of assault by his own father and half-brother that led to the removal of royal immunity in 1993, when BN also reduced further involvement of the monarchs in lawmaking. Thus, the public might be wary of returning too much power to the sultans.

The lone voice who has supported the Johor Sultan's call is former law minister Zaid Ibrahim. Others could see that while giving the monarchs more influence could balance Datuk Seri Najib's wide political powers, there are pitfalls of not holding the royals accountable once again.

Still, with no political party able to command the required two-thirds of Parliament to effect constitutional changes, the monarchs are a long way from gaining or losing any legal power.