The IAAF says it will seek a "swift reversal" of the decision that allows Olympic 800m champion Caster Semenya to temporarily compete without taking testosterone-reducing medication.

On Monday, Switzerland's federal supreme court temporarily suspended a new IAAF ruling that would restrict testosterone levels in female runners. However, the IAAF said the suspension only applied to Semenya, 28. The court's "superprovisional order" will also only apply until 25 June.

That is the date by which the IAAF must respond to the court on Semenya's case. Last month, South African Semenya filed an appeal to the court after failing to have new IAAF rules restricting testosterone levels in female runners overturned by the Court of Arbitration for Sport (Cas).

The IAAF - the governing body of world athletics - said the federal supreme court's decision was made without its knowledge, and that it was only told of the order on Tuesday. It therefore "did not have the chance" to explain why the ruling "should remain in force and applicable to all affected athletes while the appeal is pending".

It wants the supreme court's suspension of the rules to be reversed to avoid "serious confusion" among athletes and event organisers and "to protect the integrity of the sport". Read more via BBC