South Africa, New Zealand, France, India and Britain are all considering adopting standardised packaging on tobacco products but the African country hadn't previously given a timeframe.

Opponents of the law, who say it is heavy-handed and an invitation to counterfeiters, had hoped other countries would hold off from following Australia's example pending a WTO case addressing complaints by tobacco-producing countries.

"I am not even sure we can wait for that WTO decision. We can start making preparations now," South African Health Minister Aaron Motsoaledi told Reuters.

"I want it as soon as possible but realistically and most probably it would be next year," said Motsoaledi, a former smoker who quit in his final year of medical studies more than three decades ago.

Since late 2012, tobacco products in Australia can only be sold in drab, olive-coloured packets that look more like military or prison issue, with brands printed in small fonts.

The WTO put together a panel on May 5 to judge on a dispute between Australia and tobacco lobbies who say the legislation is a barrier to trade and restricts intellectual property.

The panel has six months to make its ruling but the dispute could drag on for many more months or even years if countries appeal or disagree over the level of compliance.

As well as its huge importance for the global tobacco industry, the case could have implications in other sectors, as some public health advocates see potential for plain packaging laws to extend into areas such as alcohol and unhealthy foods.

South Africa already has bold health warnings on packaging and has banned smoking in many public places but health experts want tougher restrictions, including a ban on puffing in cars when travelling with children under the age of 12 years.

"We are losing gains we've made in the last decade and it is imperative we implement plain packaging," said Priscilla Reddy, a professor at the Human Sciences Research Council in Cape Town.

"It is the only and obvious route to better public health, particularly among youth," Reddy added.

The World Health Organisation estimates that in 2012 tobacco killed six million people worldwide, 600,000 of whom were non-smokers killed by inhaling smoke passively.

Motsoaledi said he expected a fight from the tobacco industry but remained undaunted.

"They are going to be very vocal and kick dust and we are prepared to fight," he said.