Tobacco giants return to court today in their battle against the Government's new plain-packaging rules.
They suffered what anti-smoking campaigners described as a ''crushing defeat'' at the High Court in May.
The day before new regulations come into force, a judge in London declared that they were ''valid and lawful in all respects''.
Mr Justice Green rejected a judicial review action brought against Health Secretary Jeremy Hunt.
The judge declared: "There is no basis upon which I could or should strike down the regulations or prevent them coming into effect tomorrow.''
Philip Morris International, British American Tobacco, Imperial Tobacco and Japan Tobacco International had challenged the legality of the ''standardised packaging'' regulations.
The judge heard submissions that the Standardised Packaging of Tobacco Products Regulations 2015 would destroy valuable property rights and render products indistinguishable from each other.
But he ruled: "The regulations were lawful when they were promulgated by Parliament and they are lawful now in the light of the most up-to-date evidence.''
His decision that the regulations were ''justified and proportionate in the public interest'' came after Europe's highest court rejected a series of legal challenges.
Action on Smoking and Health (Ash) chief executive Deborah Arnott, said at the time: "This landmark judgment is a crushing defeat for the tobacco industry and fully justifies the Government's determination to go ahead with the introduction of standardised packaging.''
After the ruling, one of the companies, Philip Morris International (PMI) said it was ''disappointed'', but although there were ''strong grounds'', it would not be appealing.
Three Court of Appeal judges in London will now hear a challenge against the judge's ruling, expected to last four days.