Five more countries risk joining Russia on an international athletics blacklist unless they make major changes to their anti-doping programmes, the IAAF has announced.

Ethiopia, Morocco, Kenya, Ukraine and Belarus have all been given stern orders to improve by the end of the year although their participation at the Rio Olympics is not in doubt.

"The job of the council is to make sure those athletes who are going to the Games are clean under systems based on integrity" - Sebastian Coe

The IAAF announced on Friday that Russia must wait until May to discover if its suspension will be lifted in time for Rio as "further significant work" is still required to achieve compliance with anti-doping standards.

And president Sebastian Coe singled out other nations, warning: "There are no immediate sanctions - it is just a wake-up call at this point - but serious sanctions, provided for under IAAF rules, will only be considered if they don't comply with council requirements."

Russia's chances of returning in time for Rio appear to be receding after the IAAF spent two days working through the report of an independent five-man task force headed by former World Anti-Doping Agency director Rune Andersen.

Coe said: "While progress has been made, the council unanimously agreed that the Russian authorities need to undertake further significant work to satisfy the reinstatement condition, (so) RUSAF (the Russian Athletic Federation) should not be reinstated to the IAAF at this stage.

"My job is not to get as many athletes to the Olympic Games as possible. The job of the council is to make sure those athletes who are going to the Games are clean under systems based on integrity.

"There were no pre-ordained outcomes today. We were satisfied, unanimously, that more work needed to be done, although some progress has been made, before we can be asked to make the decision."

Coe confirmed the final decision on the appearance of a Russian athletics team in Rio would be made at the next IAAF council meeting, which will be convened for that specific purpose in May.

Russia was banned from international athletics in November following an expose by the German television channel ARD of inconsistencies in Russian drug testing procedures.

Coe's warning came on the day the World Anti-Doping Agency confirmed 99 positive tests for meldonium since the drug was added to its banned list in January.

WADA would not go into specific details about the sports or countries involved but its findings underline the extent of the issue in elite sport.

WADA spokesman Ben Nichols said on Twitter: "Number of Meldonium positive (Adverse analytical findings) samples today at 99 since substance was banned on 1 January 2016 @wada--ama #WADA"

Maria Sharapova revealed this week that she tested positive at the Australian Open in January, claiming she failed to click on a link outlining the updated list of banned substances sent on email by WADA in December.