Team Sky rider Jonathan Tiernan-Locke is to face disciplinary proceedings after an analysis of discrepancies in his biological passport data demonstrated an anti-doping violation, the International Cycling Union has announced. .
The Devon rider, who joined Team Sky after winning the 2012 Tour of Britain, pulled out of the World Championships earlier this year after being asked to explain his results by the UCI.
"The analysis of the biological passport of Mr Jonathan Tiernan-Locke by the Experts Panel has demonstrated an anti-doping rule violation (use of prohibited substances and/or methods)," a UCI statement said.
"Consequently and in compliance with the UCI Anti-Doping Rules, the UCI has requested his National Federation to initiate disciplinary proceedings."
The 28-year-old from Plymouth has vowed to contest the charges and denies all wrongdoing.
A statement released by Tiernan-Locke's management company read: "Jonathan Tiernan Locke was notified that the UCI wish to instruct British Cycling to instigate proceedings against him regarding an abnormality in his biological passport.
"Mr Tiernan Locke vehemently denies the charges brought against him and has informed the UCI that he fully intends to contest them.
"Mr Tiernan Locke will not ride for Team Sky, attend training camps or undertake any team duties until a decision is made in these proceedings.
"Mr Tiernan Locke is looking forward to a speedy and just resolution of these unfortunate charges. Until a decision has been reached, Mr Tiernan Locke will make no further comment on the matter."
Tiernan-Locke withdrew from the Great Britain team for the Road World Championships road race at the end of September, citing poor form.
But on the day of the event it was revealed he had withdrawn from competition over "possible discrepancies" in his biological passport.
Team Sky, which has a zero-tolerance policy to doping, on Tuesday reiterated its stance from September, insisting the period in question occurred prior to his employment with them.
A statement on teamsky.com read: "We understand that the violation was highlighted by an anomaly in his Biological Passport, in a reading taken before he signed for this team.
"There are no doubts about his approach or performance in Team Sky. This is a team that trains, races and wins clean.
"Jonathan Tiernan-Locke will not ride for Team Sky or take part in any team activities - including training camps and all team duties - until a decision is made in this disciplinary hearing process.
"At this stage, we will add no further detail until this initial disciplinary process is concluded."