Oscar Pistorius can compete against the world's best able-bodied athletes while researchers decide if his prosthetic legs give him an unfair advantage.
South African Pistorius, 20, wants to compete at the Olympics
In March, athletics' governing body introduced a rule banning any runner deemed to benefit from artificial help.
But it now appears it has changed its stance, to the benefit of Pistorius.
The 20-year-old South African runs using carbon fibre curved blades after his legs were amputated from below the knee when he was just 11 months.
He was born without fibulae in both legs due to a congenital condition.
His major objective is to compete at an Olympics, but an International Association of Athletics Federations (IAAF) spokesman said such talk was premature.
He has also yet to run times that would allow him to qualify for the Beijing Games.
We have nothing against disabled athletes, on the contrary, but we need to be fair
He has clocked 10.91secs in the 100m, 21.58secs in the 200 and 46.56secs in the 400 - all world records for disabled athletes.
He also finished second in the 400m at the South African Championships - the able-bodied meet - in March.
IAAF spokesman Nick Davies said the organisation was going to take it upon itself to work with Pistorius to conduct scientific research and tests on the runner and his prosthetics.
Davies said one of the aims was developing criteria on prosthetics and other aides.
"Perhaps certain prosthetics will be allowed and others won't," he said.
"We need to establish the facts and we want to do this together. We have nothing against disabled athletes, on the contrary, but we need to be fair."
Pistorius has been dubbed 'Blade Runner' because of his prosthetics
Davies said Pistorius's case was taking the federation into new and unfamiliar territory.
"This issue is so new," said Davies.
"Oscar is an exceptional athlete, maybe unique. He is on the very edge of disabled and able-bodied sports. No one else has ever done that, that is why we are in the dark."
Pistorius, dubbed 'Blade Runner' because of the slimline curved prosthetics, is adamant his blades give him no advantage or extra energy and that his stride is no longer than anyone else's.
"They are passive devices," he said. "If anything I am at more of a disadvantage. I have no ankles. There is less blood flowing through my body. I have no calf muscles so I have to use more muscles to do what they would.
"These exact feet have been used for 14 years and there has never been a paralympic sprinter to run my times."