Caster Semenya has the “unqualified support” of Athletics South Africa (ASA) in her court case against athletics’ governing body, the IAAF.
Olympic 800m champion Semenya, 28, is challenging a proposed rule by the IAAF that would restrict the levels of testosterone in female runners.
The IAAF denied a report on Thursday that lawyers would argue athletes like Semenya should be classified as male.
The ASA said it had a “constitutional obligation” to contest the rule.
“Athletics South Africa has reaffirmed its total commitment to back and fight alongside Semenya,” a statement read.
“As South Africans, we all have a constitutional obligation to contest any infringements of human rights, shaped by our experiences under apartheid.”
Apartheid was a system of racial segregation imposed by a minority white ruling group in South Africa from 1948 to 1991.
The proposed IAAF rule would apply to women who race in track events from 400m up to the mile.
Under the ruling, female athletes with naturally high testosterone levels would have to race against men or change events unless they took medication to reduce it.
Athletes who wanted to compete in those events must take medication for six months, then maintain a lower testosterone level.
The rules were intended to be brought in on 1 November last year, but were delayed until 26 March after the legal challenge from Semenya and ASA.
Speaking in June, Semenya called the ruling “unfair”, adding: “I just want to run naturally, the way I was born.”
As an 18-year-old, she was asked to take a gender test but no results have officially been made public.
The case will be heard at the Court of Arbitration for Sport (Cas) from 18-22 February, with an outcome expected by 29 March.