Athletics' global governing body said Saturday it had given the Russian federation an additional five months to produce a comprehensive plan to fight doping and be reinstated to the sport or face expulsion.
World Athletics had originally given the Russian federation (RUSAF) until the end of this month to come up with the plan but it has now set a new deadline of March 1, 2021.
World Athletics said it was granting Russia more time because "RUSAF currently does not have the resources available to produce a detailed and appropriate plan for reinstatement".
The new deadline is less than five months before the start of the Tokyo Olympics, raising fresh doubts about Russian athletes' participation in the Games.
Russia has been suspended from track and field since November 2015 after the World Anti-Doping Agency (WADA) found evidence of widespread drug use.
In 2018, the Russian federation submitted falsified documents to justify the whereabouts of world indoor high jump champion Danil Lysenko after the breached anti-doping rules, leading to the eventual departure of senior officials.
World Athletics fined Russia $5 million plus costs of $1.31 million, which the federation paid in August, but the global body also made its reinstatement conditional on the federation, now under new leadership, setting out a roadmap showing it has "a culture of zero tolerance for doping".
World Athletics said on Saturday that while RUSAF had submitted a draft plan that was "better than what has come before" it was still "seriously deficient", so it was setting the new deadline.
The organisation's anti-doping Taskforce said in a statement: "This failure appears to be due not to a lack of willingness but rather a lack of know-how and resources.
"There is currently a void at RUSAF -- they have no board, no senior management, and very few experienced staff. They need to fill that void urgently with people who share the vision to change the culture of the organisation and the sport, and who have the skills to do so."
World Athletics president Sebastian Coe warned: "If an adequate plan is not completed by then, the (World Athletics) Council will once again consider the matter of RUSAF’s expulsion."
To assist RUSAF, World Athletics has appointed Dr Margarita Pakhnotskaya, the former Deputy Director-General of the Russian anti-doping agency RUSADA, as one of two experts based in Russia.