Four of the world's biggest tobacco firms have launched a legal bid to challenge the Government's new plain packaging rules.Read the full story ›
Plain packaging for cigarettes has been given the go-ahead after the plans were approved in the House of Lords.
Peers backed the plans without a vote after MPs voted in favour last week.
The new regulations will come into force from next year.
Health minister Earl Howe said it was an important step towards a "smoke-free generation".
Japan Tobacco International (JTI), the company behind Benson & Hedges and Silk Cut, has said it considers plans for standardised cigarette packaging "unlawful" and will challenge the legislation in court.
In a statement issued after MPs voted to approve plain packaging in a free vote in the House of Commons, JTI's managing director Daniel Torras said the law had "been rushed through Parliament, with little regard for proper scrutiny and debate."
The Government is using the General Election as the finishing line and has hurried this policy along, stifling debate among MPs and giving little opportunity for opposing views to be aired.
Controversial regulations enforcing standardised tobacco packaging have been approved by MPs by 367 to 113, in a landmark free vote in the House of Commons.
Peers will be asked to vote on the regulations on Monday and, if they approve them as expected, the new rules will come into force in May 2016.
The regulations have been bitterly opposed by some on the Conservative benches and the number of 'No' votes is higher than had been forecast.
David Cameron's official spokesman said: "The Prime Minister voted in favour of this change. He is pleased that it has gone through."
Asked if the PM was disappointed at the number of Conservative MPs voting against plain tobacco packaging, the spokesman said: "The whole point of a free vote is that people can express their views freely."
Public health minister Jane Ellison told the Delegated Legislation Committee the regulations for plain packets for cigarettes would bring the country "one step closer to our first smoke-free generation".
The Government has no intention to extend standardised packaging to any other product than tobacco.
Tobacco is a uniquely harmful consumer good and as such it's been treated uniquely in regulatory terms for many years.
The Conservative frontbencher said she recognised concerns that standardised packaging for cigarettes could be a "slippery slope" towards a similar approach to other products such as junk food and alcohol.
MPs are to hold a crucial vote later on controversial plans to introduce plain cigarette packets.
Powers for standardising packaging were in the Children and Families Act 2014, but the Commons must approve bringing them into force.
The regulations were discussed and agreed by a committee earlier this week and will now be subject to a free vote on the floor of the House. But as they are not primary legislation, there will be no further debate.
There have been suggestions that more than 80 Tories could be among those opposing the plans - which critics argue will not prevent people smoking, are being introduced too hastily, and could confuse consumers.
Shadow Health Secretary Andy Burnham has praised Jeremy Hunt for setting a "clear timetable" for introducing standardised plan cigarette packaging.
Deputy Prime Minister Nick Clegg has backed plans to introduce plain cigarette packaging, saying there is evidence it does help minimise marketing appeal.
Speaking on LBC Radio, Mr Clegg said: "It's not a crime but it's very bad for you, and we should be taking sensible steps to discourage people - particularly kids - from taking up smoking.
He added: "There is evidence, and I think it's been borne out by the latest facts in Australia, that it does help minimise the marketing appeal."
Ukip leader Nigel Farage has hit out at Government plans to introduce standardised plain cigarette packaging, saying it could lead to worse health outcomes than we have now.
Mr Farage accused MPs of attempting to rush the legislation through ahead of the general election and claimed it would be "ineffectual".
This legislation is wrong, not only is it counter to freedom, the basic building block of prosperity, but it is an abuse of Parliamentary process, and most important of all, it is ineffectual and in fact could lead to worse health outcomes than we have now