Chelsea and Manchester City are in pole position to land Radamel Falcao as the striker's contract contains a clause designed to deter Real Madrid from luring him across the Spanish capital.
Falcao, who struck 72 goals during a prolific two-year spell at Porto, has netted 63 times since switching to Atletico Madrid at the start of last season.
He is widely considered to be the finest out-and-out centre-forward in the world and is coveted by Europe's richest sides, with Chelsea, City and Real Madrid all keen to tempt him away from the Vicente Calderon in the summer.
Atletico, who are resigned to the fact he is likely to leave at the end of the season, are determined to ensure he does not move to their deadly rivals Real.
And, according to AS, a clause in the Colombian's contract states the Spanish champions must pay an eye-watering £65m to land him - a fee which is £13m higher than the amount Atletico would accept from City or Chelsea.