LONDON, England - Christian Horner is being hotly tipped as the next 'F1 supremo' should - when - Bernie Ecclestone stand down.A source at Delta Topco, the CVC-controlled group that owns the sport's commercial rights, has named 40-year-old Briton Horner as the top choice to succeed the embattled chief executive.The news follows suggestions that external figures such as outgoing Sainsbury's chief Justin King or F1 marketing specialist Zak Brown are the more likely choices.HORNER: 'NOT MY JOB'Horner, Red Bull team boss, has repeatedly denied he is interested in the job, even after a judge in February 2014 damagingly found that Ecclestone had paid a bribe to Gerhard Gribkowsky. If convicted in Germany later in the year the F1 board would certainly remove the now 83-year-old.Horner, however, said last week he would "never consider" replacing Ecclestone. He told Sportbusiness International: "My function and commitment is to Red Bull, I certainly hope Bernie will continue for another 20 years." However, even in light of Horner's repeated denials, a source close to the Delta Topco board said: "There is no doubt Christian fits the bill. We need somebody with experience of F1, who can deal with TV rights and commercial contracts," the source told The Times newspaper."The fact that Bernie would train Christian looks like a solution to many of the directors." Stay with Wheels24 for the 2014 F1 season – fresh reports every day.