Four of the world's biggest tobacco firms are to begin a legal challenge to the government's new packaging rules.
The regulations will ban companies from using any logos or branding on packets of tobacco products from May 2016.Philip Morris International, British American Tobacco, Imperial Tobacco and Japan Tobacco International say it will unlawfully take away their trademark intellectual property.
The government argues the measure will discourage more people from smoking.
Under the new "standardised packaging" regulations, any part of tobacco packaging not covered by the health warning carried on it must be a dark brown or green colour.
Brand names must be in small, non-distinctive lettering.
The four major tobacco companies argue the regulations will destroy their highly valuable property rights, and render products indistinguishable from each other.
'Robust defence'
They claim the regulations violate a number of UK and EU laws, and that data from Australia, which brought in plain packaging in 2012, fails to prove such a move reduces smoking rates.The Department of Health is fighting the High Court challenge, which is due to begin on Thursday.
It says the change is an important public health measure aimed at discouraging children from smoking and helping smokers to quit.
"Smoking is catastrophic for your health and kills over 100,000 people every year in the UK, with the burden of disease falling most heavily on poorer communities," a spokesman said.
The government would "robustly" defend the policy, and had powerful arguments in its favour, he added.
The department cited an independent review by Sir Cyril Chantler in 2014, which concluded that it was "highly likely" that standardised packaging would reduce the rate of children taking up smoking, and "implausible" that it would increase tobacco consumption.
