It comes after appeals against a World Athletics regulation, which does not allow her and other female athletes suffering from Differences in Sexual Development (DSD) to compete in events from 400m to one mile (1600m) without reducing their testosterone levels, failed in both the Court of Arbitration for Sport (CAS) in April 2019 and Swiss Federal Supreme Court in September 2020.
A statement issued by Norton Rose Fulbright, who represent Semenya, said: "We will be taking World Athletics to the European Court of Human Rights and public support goes a long way to help show how the rules from World Athletics are against public interest."
World Athletics have repeatedly said that the regulations are aimed at creating a level playing field for all athletes.
"World Athletics has always maintained that its regulations are lawful and legitimate, and that they represent a fair, necessary and proportionate means of ensuring the rights of all female athletes to participate on fair and equal terms," the governing body stated after the ruling of the Swiss Federal Supreme Court came out.
The World Athletics rules state that any athlete with DSD – a condition that sees the body naturally produce higher levels of testosterone than women who do not have DSD – who wants to run distances between 400m and the mile must take medication to suppress their testosterone levels, and maintain those reduced levels for a certain period of time.
Aside from Semenya, the other two runners behind her on the women's 800m podium at Rio 2016 – silver medallist Francine Niyonsaba of Burundi and bronze medallist Margaret Wambui of Kenya – are both also affected by the regulations among other athletes.
After losing her Swiss Supreme Court appeal in September, the South African said: "I am very disappointed by this ruling, but refuse to let World Athletics drug me or stop me from being who I am. Excluding female athletes or endangering our health solely because of our natural abilities puts World Athletics on the wrong side of history."
Since then, South Africa's national Parliament has passed a motion condemning World Athletics, calling their restrictions an "injustice and violation of human rights".
"We greatly appreciate the support of the Parliament of South Africa, the highest legislative body in South Africa, and commend their willingness to take action by resolving to help protect the rights of a fellow South African." – Statement from Caster Semenya's lawyers
"With growing support from institutions and bodies across the globe, we remain hopeful that World Athletics will see the error it has made and reverse the prohibitive rules which restrict Ms Semenya from competing," the statement from Norton Rose Fulbright continued, citing support from the African Commission for Human and People Rights.
"The increasing number of institutions that have shown their support for Ms Semenya reinforces that it is not acceptable to require a black, or any other woman, to either have invasive surgery or unethical hormonal treatment to curtail natural biological functions, to compete.
"We encourage everyone to help create a more equal world by showing their support on social media and by putting pressure on their sporting bodies to embrace and apply internationally accepted human rights values in their activities and rules."
Semeya ran a race over the non-Olympic 300m distance in February. She has also run two 200m races this year, setting a time of 23.49 seconds in Pretoria in March, although the time was not recognised as her personal best due to lack of wind information. A week earlier, she had run 23.81 seconds on the same track.
The 200m Tokyo 2020 qualification standard is 22.80 seconds.