Tobacco industry powerhouses British American Tobacco (BAT) and Imperial Tobacco start on Monday due diligence study exercises at the cigarette mills of Bulgaria's privatisation-bound tobacco monopoly Bulgartabac. Philip Morris International will shortly follow suit. The three candidates eyeing Bulgartabac's four most attractive cigarette factories bought on Friday the tender participation documentation, paying 25,000 euros for the papers of each of the two pools into which the mills are grouped. The first pool includes the mills Blagoevgrad BT and Stara Zagora-based Sluntse BT that will be sold together with the Victory, Prestige, Melnik, Nevada, Country, Verea and Shipka brands. The other pool features the Sofia BT and Plovdiv BT mills together with the Sredets, Tresor, New Line, MM, Femina and Arda brands. The two pairs will go to different buyers. Philip Morris, BAT and Imperial Tobacco have until September 30 to submit their binding offers. Before that they will have to come up with a 1 mln euro bank guaranty. The government hopes that the management of Bulgartabac holding company - under the cabinet's supervision - will manage to pull through with the sell-off of the four mills by the end of the year.