Aisling Burnand, executive director of policy and public affairs at the influential charity, spoke to PRWeek for this week's public affairs supplement.
Burnand said: 'It is challenging that the tobacco industry comes in many guises ... You might know the person who has just walked in works for a tobacco company, but they might be representing another group. And we know a lot of research is funded by the tobacco industry.'
Her comments come weeks after British American Tobacco admitted funding a separate campaign against government plans to ban cigarette displays in shops.
It was reported in February that BAT had admitted in a letter to Labour MP Kevin Barron that it had provided funding to the National Federation of Retail Newsagents' campaign. Barron wrote to Health Secretary Andrew Lansley warning of 'covert lobbying by the tobacco industry'.
BAT has denied underhand tactics, but Burnand told PRWeek she was keen to ensure MPs were not hoodwinked: 'What we have to do is ensure that the people we're talking to recognise that not every lobbyist may be all that they appear to be.'
Burnand also spoke about her own no-nonsense approach to lobbying, stressing: 'Most MPs don't just want a cosy chat.'
See supplement with this issue.