Guardian News and Media/London

Confidential documents leaked to the Observer reveal how the world’s largest tobacco company sought to kill the government’s plans to introduce standard packs for cigarettes, using a sophisticated lobbying campaign that targeted key politicians and civil servants who it believed were supportive of its views.

Documents circulated within Philip Morris International (PMI) last February and March, marked “for internal discussion and illustration purposes only”, show how the owner of the Marlboro brand drew up an astonishingly detailed attack plan to “ensure that PP (plain packaging) is not adopted in the UK”.

This goal explicitly contradicts big tobacco’s public position, presented to the government, that there was a need to assess how the measure had been received in Australia, where unbranded packs were introduced last year, before a decision was made on whether it should be copied in the UK.

The tobacco lobby fears that if the UK were to introduce plain packaging, other countries would not be far behind, and it has spent millions of pounds seeking to derail the proposal.

PMI’s role in lobbying government is now under acute scrutiny after it emerged that last November it hired the Conservative party’s election strategist, Lynton Crosby, who has extensive tobacco industry connections, to help it make its case against plain packaging.

Crosby has denied having any conversations with the prime minister about plain packaging.

The PMI documents reveal that, in a bid to swamp the department of health’s consultation exercise on plain packs with supporting arguments, the company boasted that it had the “potential” to help generate more than 18,000 responses, including 6,000 from its recruited group of smokers, 950 from industry, 10,050 from its “retail group”, 40 from thinktanks and 1,000 from a trade union, believed to be Unite.

The internal documents reveal how, over the past year, PMI sketched out a timeline for rolling out its key messages.

These included the claim that plain packs would make the illicit trade in tobacco worse and the need for the UK government to “wait and see what happens in Australia (for two or three years) before walking into the unknown with no evidence it will reduce smoking”.

The latter message was echoed by the government when it announced that it was abandoning the plan to introduce plain packs.

The department of health’s statement said: “The government has decided to wait until the emerging impact of the decision in Australia can be measured before we make a final decision.”

The company appointed polling agency Populus to ask 1,000 voters in each of the Tories’ 19 most marginal seats for their views on government policies.

Voters in constituencies such as Lincoln, Dumfriesshire and Enfield North were given a list of issues and asked to prioritise the three the government should focus on.

Most suggested the economy, education and unemployment. Only 3% went for action on smoking. The voters were also asked: “When it comes to reducing smoking rates in the UK, where should the government focus its effort?” Almost two-thirds 62% said “better education”, while less than one in four 24% suggested introducing plain packaging. The exercise helped the tobacco company to work out what claims would play well with the public and the government. PMI’s assessment of the results notes.

“The data supports the narrative that there are bigger problems in the UK to focus on than plain packaging, but if focused on smoking issues, there are other initiatives that would more effectively reduce smoking rates.”

PMI drew up an extraordinarily detailed spreadsheet listing the position it believed every single MP, special adviser and cabinet minister, as well as several strategically important civil servants, held on the issue of plain packs. Whether PMI or its advisers had any inside knowledge of their thinking is unknown.