Red Bull team principal Christian Horner believes Aston Martin's high-profile unveiling of Adrian Newey was "premature" as he is still under contract with the Milton Keynes team.
Since it was announced Newey would be leaving Red Bull, speculation over his next destination was rife but he ultimately ended up signing a deal to be Aston's new technical managing partner for a reported £30 million a year, as well as becoming a shareholder.
