In a statement, the IAAF, which hosted a meeting in Lausanne to discuss the topic, said IF officials were in agreement with eligibility rules passed by the worldwide body last month.

Under IAAF regulations, the concentration of testosterone in an athlete must be less than five nanomoles per litre continuously for a period of at least 12 months prior to being declared eligible.

The International Olympic Committee (IOC) regulations state athletes who transition from male to female can compete in the women's category without requiring surgery, provided their total testosterone level in serum is kept below 10 nanomoles per litre.

The IAAF's previous limit was 10 nanomoles.

The IOC eligibility guidelines are used by several IFs to determine their own rules, but the organisation is looking into establishing stricter criteria.

It is believed, however, that this will not be in place before next year's Olympic Games in Tokyo.

"Testosterone is the primary known driver of the performance gap between males and females and serum Testosterone is regarded as an acceptable proxy to distinguish male from female athletes," the IAAF said.

"If a federation decides to use serum Testosterone for this purpose, it should adopt a fixed threshold at or below 5nmol/L for eligibility for the female category."

The group, which included representatives from the IAAF, International Paralympic Committee, International Tennis Federation, World Rowing and the International Golf Federation, said the inclusion of transgender athletes "within the female category should be promoted with meaningful eligibility standards, provided it does not create intolerable unfairness".

At the meeting, the officials agreed it should be up to the respective IFs to design "sport-specific" rules on transgender athletes.

They agreed to establish two working groups, one of which is designed to "help the interested IFs to draft their own transgender eligibility regulations/rules".

The other will "establish a medical and scientific network to promote multicentre applied research on transgender athletes, and more specifically to study the effect of hormone therapy along with other transgender-specific medical interventions on the physical and mental drivers of athletic performance and their effects on the integrity of sporting competition", according to the IAAF.

The IAAF's updated guidelines bring them into line with those which apply to athletes with differences of sexual development, such as South Africa's world and Olympic 800 metres champion Caster Semenya, who is currently ineligible to compete as she pursues legal options to reverse the current IAAF ruling.