Tobacco companies challenging the new packaging rules in Australia will have to wait for some more time to see whether they have been successful after an Australian court delayed their decision on a later date.
Four cigarette companies, led by British American Tobacco (BAT), have contested the new law in a High Court hearing, claiming it infringes their intellectual property rights by banning brands and trademarks from packets.
The government has said it is confident it will see off the challenge to the legislation, which will see all cigarettes sold in the same drab olive-green packets and graphic health warnings from December 1.
Chief judge Robert French said the court would retire to consider its position and return judgement in the closely-watched case at a future date. It was not clear when the decision could be expected.
Closing arguments in the case saw lawyers acting for Japan Tobacco International (JTI) producing a packet of rat poison in court, saying warnings for the toxic substance were modest compared with those planned for cigarettes.
Government lawyers had argued that the new laws were similar to the regulation of other harmful substances such as rat-killer.
Australia is the first country to mandate plain-packaging, but the ground-breaking move is being closely watched by other countries considering similar approaches, including Britain and Canada.
New Zealand said Thursday it had agreed "in principal" to go ahead with laws mandating similar plain packaging, subject to public consultation later this year as part of a wider strategy to stamp out smoking in the country by 2025.
Canberra says its plan is aimed at reducing smoking-related deaths, but JTI, British American Tobacco, Imperial Tobacco and Philip Morris have argued that it infringes their trademark rights.
Australia estimates it has 15,000 deaths each year from tobacco-related illnesses.