Puffs of white smoke emerged from the Bristol headquarters of Imperial Tobacco today as Alison Cooper was promoted to chief operating officer, making her a clear front-runner to succeed long-standing chief executive Gareth Davis.

Cooper, 42, has been at Imps for 10 years and was in charge of the integration of Altadis, taken over for €16.2 billion (£15 billion) two years ago.

That deal brought together the world's number four and five tobacco companies and gave Imperial major growth opportunities in new emerging markets.

Chairman Ian Napier said: "Alison has extensive commercial experience and has made a significant contribution to the success of Imperial Tobacco. She will focus on driving the operational performance and strategic direction of the business, ensuring we maximise our long-term future growth."

Davis, 58, has run Imps since he led its demerger from Hanson in 1996. He is a heavy smoker, while Cooper, who is married with two daughters, is described as an "occasional smoker".

She graduated from Bristol University in 1988 and joined accountants PricewaterhouseCoopers, where she worked on several deals for Imperial before joining the cigarette giant in 1999.

Imperial said it expects results for the year to September to be "in line with management expectations". Targets for savings from the Altadis deal remain unchanged at €180 million by the end of this year. A later than usual Budget means the pre-Budget increase in stocks of cigarettes by retailers will fall in the company's second half rather than the first as usual.

There are only three women chief executives of FTSE 100 companies: Dame Marjorie Scardino at Pearson, Cynthia Carroll at Anglo American and Dorothy Thompson at Drax.