No anti-doping charges will be brought in relation to the contents of a Jiffy bag delivered from British Cycling to Team Sky, as a UK Anti-Doping (UKAD) investigation concluded that it was “impossible” to fully determine what was in the bag.

UKAD opened its investigation in September 2016 after receiving information that a mysterious Jiffy bag delivered from British Cycling headquarters in Manchester to Team Sky at the 2011 Critérium du Dauphiné could have contained triamcinolone, a glucocorticoid which is banned in-competition when administered in certain ways.

Giving evidence to MPs as part of an inquiry into doping in sport in December 2016, Team Sky boss Dave Brailsford said that the package had contained the decongestant Fluimucil, having been told that this was the case by British Cycling doctor Richard Freeman. However Dr Freeman did not have medical records to prove that this was the case.

As part of its investigation, UKAD interviewed 37 individuals connected to British Cycling and Team Sky and examined “a voluminous amount of documentation”, drawing a number of conclusions, but being unable to confirm the contents of the package.

The investigations found that at some point during the Critérium du Dauphiné, Dr Freeman, who was working for Team Sky at the time, had requested that a package be sent out to France, and that then technical director Shane Sutton had arranged for then coach Simon Cope to deliver the package.

Cope then travelled to France where he delivered it to Dr Freeman. Dr Freeman said that the package contained Fluimucil, and Bradley Wiggins recalled that he had been treated with Fluimucil on the evening of June 12, after the final stage of the Critérium du Dauphiné, but said that he did not know what was he in the package.

The investigation concludes: “Put simply, due to the lack of contemporaneous evidence, UKAD has been unable to definitively confirm the contents of the package. The significant likelihood is that it is now impossible to do so.”

British Cycling and Team Sky have both issued statements welcoming the conclusion of the investigation and reaffirming their commitment to clean sport.