The employment minister, Priti Patel, was part of a team of spin doctors paid hundreds of thousands of pounds to help a tobacco giant counter negative publicity, including that surrounding its joint venture with one of the world’s most brutal military regimes.

Documents unearthed by the Observer shine new light on Patel’s work for Shandwick, a lobbying and PR firm that worked for British American Tobacco (BAT) in the early years of this century.

The documents, released by BAT following a legal action, show that Patel was one of seven employees used by Shandwick on the account. One of her jobs was to lobby MEPs against the introduction of the EU tobacco control directive, which was introduced shortly after the new millennium. She was charged with ensuring that a letter from the BAT chairman at the time, Martin Broughton, outlining his objection to the directive, was faxed to every MEP.

But internal BAT documents show that in addition to her work lobbying MEPs, Patel’s team played a key role in fashioning the company’s public profile. In a memo dated 14 December 2000, a senior executive within the company, Andreas Vecchiet, conducted an annual appraisal of the Shandwick team’s performance. “We have mainly used Shandwick for project-based work relating to the WHO [World Health Organisation] campaign, NGO monitoring … reputation issues relating to Burma, and some limited advice relating to Nigeria and labour standards.”

BAT’s position in Burma at the turn of the millennium was hugely controversial. “BAT’s factory in Burma was jointly owned with the military dictatorship and so helped fund one of the most brutal military dictatorships in the world,” said Anna Roberts, executive director at Burma Campaign UK. “BAT refused to admit how much money it gave to the dictatorship, but Burma Campaign UK estimated that BAT paid the generals $16m (£10m) in taxes alone between 1999 and 2002. In contrast, BAT paid its factory workers in Burma just £15 a month. The dictatorship spent 40% of its budget on the military.”

Following widespread public outrage, BAT pulled out of Burma in 2003.

The tobacco giant also came under fire in Nigeria after children as young as seven were found to be working on farms supplying it with tobacco leaf. BAT insists it has always been opposed to the use of child labour. It has taken extensive steps to ensure that child labour is not used in the production of its cigarettes, in particular the use of random inspections. However, some labour organisations have expressed concerns that the practice is continuing.

Despite Shandwick’s efforts, BAT was not impressed with the team’s performance, notably on its work regarding Burma. “The main issues we have are lack of timeliness and responsiveness,” Vecchiet notes. “We find the accuracy of information from basic raw material is often lacking.”

He adds: “On work we commission – such as on Burma … they have had to be sent back to be overhauled, made more comprehensive and sophisticated.”

It appears that many within the Shandwick team were opposed to working for “big tobacco”. “Virtually since day one we have felt a sense that Shandwick does not actually feel comfortable or happy working for BAT,” Vecchiet complains.

He mentions a request from one Shandwick employee for BAT not to refer to Shandwick as its PR agency in a magazine article. But he notes that “Priti [and another employee] seem quite relaxed working with us”.

Patel was 27 when she joined Shandwick and it is not clear whether she still defends her former employer’s work for BAT. She worked for Shandwick for three years and was a junior employee who had no control over the BAT account, which was a significant earner for her employer.

The documents show that in 2001, Shandwick drew up plans to invoice BAT for 279 hours of its work a month, of which Patel’s contribution amounted to 100 hours. BAT was charged £165 an hour for Patel’s services. The entire team was on a monthly retainer of nearly £40,000 – a total of almost £500,000 a year.

The Observer has repeatedly asked Patel for comment, but she has declined to do so and in the past has referred the matter to a law firm.

Patel is seen as on the right of the Conservative party, having backed calls for the return of capital punishment and voted against same-sex marriage. She is also seen as a serious force in the party.