The South African government has pledged its support for Caster Semenya after the Court of Arbitration for Sport dismissed her appeal challenging the new IAAF rules regulating testosterone in female athletes.

Under the new rules, female athletes classed as having differences in sexual development (DSDs) will have to reduce their blood testosterone level to below 5 nmol/L for six months before they can compete in events ranging from 400 metres to a mile. They must then maintain it below that level continuously.

The IAAF argues the rules are essential to preserving a level playing field.

The South African government expressed disappointment with the judgment, which it said it would study in full before determining a way forward.

“As the South African government, we have always maintained that these regulations trample on the human rights of Caster Semenya and other women athletes,” a statement by the Minister of Sport and Recreation Tokozile Xasa read.

Xasa expressed her gratitude to South Africans and various sector players for their overwhelming support of Semenya amidst the ruling by the CAS.

Xasa also called upon Athletics South Africa (ASA) to take the matter up in the General Council of the IAAF and lobby other national athletics associations to internally oppose the new regulations.

ASA says it is considering approaching the Swiss Federal Tribunal within 30 days as stipulated in the ruling. Semanya could also take her appeal up to the European Court of Justice.

Semenya has dominated the women's 800 metres race over the last decade, a period in which she became a favourite among South African athletics fans.