A blanket ban on corticosteroids, the drug at the heart of controversies involving former Tour de France winner Bradley Wiggins and All Blacks rugby legend Dan Carter, is being considered by the World Anti-Doping Agency (WADA), it was revealed on Wednesday.

Such a ban would make it more difficult to receive a Therapeutic Use Exemption (TUE) which Wiggins successfully utilised on three occasions for the corticosteroid triamcinolone to treat asthma.

One of those TUEs was issued in 2012 when he became the first British winner of the Tour de France.

Carter, alongside fellow New Zealand international Joe Rokocoko and Argentina wing Juan Imhoff, is being investigated by the French Anti-Doping Agency over the use of corticosteroids in last year's Top 14 rugby final where he appeared for Racing 92.

WADA director general Olivier Niggli, speaking to a small group of journalists after appearing on a panel at the Tackling Doping in Sport conference, accepted the issue needed to be addressed.

"It is an unsatisfactory situation, the current one, we all agree on that," said Niggli when asked whether or not UK Anti-Doping's (UKAD) calls for a blanket ban found favour with WADA.

"We have set up a group to try to come up with a better proposal on how we can do that.

"We had hoped for a number of years that research would bring us detection methods that would distinguish the route of administration (rubbing on cream is legal).

"The reality is that it doesn't seem too easy to come up with a method allowing us to do this."

Niggli said the time had come to change tack.

"This has been dragging on for a number of years to get that research and it hasn't happened," he added.

"We are now at a stage we have to have another discussion. In my view the system as it is now is not good -- only the people who are being so called 'honest' about what they are doing are getting caught."

Nicole Sapstead, chief executive of UKAD, welcomed the news.

"I think they're in a fantastic position to carry that piece of research forward," said Sapstead.

"I'm not party to how corticosteroids are used other than for UK athletes and therefore they are in a great position to see it from an international perspective.

"If they were to introduce an outright ban then great."

Sapstead said UKAD had requested three times for corticosteroids to be put on the prohibited list, chiefly because they didn't think the athlete's medical needs demanded such treatment.

"Some corticosteroids aren't always being administered in a way that's reflective of an individual's actual medical needs," said Sapstead.