Chelsea owner Roman Abramovich is happy to back a major spending spree by manager Andre Villas-Boas.
The Mirror says Marseille right-back Cesar Azpilicueta, who is likely to cost around £12million, is being lined up to fill a gaping weakness in the Blues' defence.
The £7m signing of Bolton and England centre-back Gary Cahill, meanwhile, is expected to be completed in the next 48 hours at the start of a busy month that will see a revolving door policy at the club.
Initial talks with Marseille have been held over 22-year-old Azpilicueta, who is only third-choice at his position for star-studded world champions Spain but has impressed in his second season in French football after a £8m move from his homeland's Osasuna in 2010.
Villas-Boas is also seeking extra firepower up front to cover for the imminent departure of striker Nicolas Anelka to China.
The Blues are also continuing to monitor £30m-rated Uruguayan striker Edinson Cavani, who has impressed this season for Napoli, who face the west Londoners in the Champions League's last 16 next month.