Chris Froome
Chris Froome is a former teammate of Sir Bradley Wiggins Getty Images

Chris Froome has admitted doubts remain over Sir Bradley Wiggins' use of therapeutic use exemptions (TUEs). A recent computer hack by the Fancy Bears group revealed that the 36-year-old cyclist has applied for a number of TUEs for allergies and respiratory issues.

Sir Bradley has defended his use of the anti-inflammatory drug triamcinolone – which is a banned substance – shortly before the 2011 and 2012 Tour de Frances and the 2013 Giro d'Italia, saying the drug put him back on "a level playing field".

But Froome, Sir Bradley's former teammate, said "questions remain" about the use of TUEs. "It's impossible to say if he was operating in a grey area," the three-time Tour de France winner said, according to cyclingnews.com.

Sir Bradley's TUEs were all approved by cycling's world governing body, the UCI, and the relevant authorities in the UK. However, Froome has revealed he did not know Sir Bradley suffered from allergies.

"I knew he had asthma, but I wasn't aware of his allergies," said Froome, 31. "Questions remain over his symptoms, the choice of treatment and the related performance benefits from that treatment. It's a great shame for the sport that we're once again debating the validity of a Tour de France victory."

Froome's comments come shortly after Sir Dave Brailsford, the boss of Team Sky, admitted he was "not proud" of the way he has dealt with speculation surrounding Sir Bradley. Sir Dave, 52, defended the Olympic gold-medal winning star after his medical records were leaked into the open, but the cycling chief said he has made things a "damn sight worse".

"I'm not proud of the way I dealt with this," Brailsford recently explained to the Telegraph Cycling Podcast. "I have been through a lot of questioning and scrutiny. It's not comfortable. But if I didn't think we were doing it the right way, I wouldn't be here."

Athletes are granted TUEs in circumstances whereby there is a genuine medical need for them to take a banned substance and an alternative treatment is not available.