FIFA tried to contact Russian whistleblower Grigory Rodchenkov over accusations of doping in Russian football and will do so again after samples have been re-tested by the World Anti-Doping Agency (WADA), world football's governing body told AFP.
Rodchenkov's lawyer said his client had information that could be of interest but claimed FIFA had not made any attempt to contact the man who was the source of revelations about state-sponsored doping in the host nation of the 2018 World Cup.
Contacted by AFP, FIFA said they had tried to get hold of Rodchenkov via WADA before November 22 this year, only to be told he was not available.
Now FIFA are waiting for WADA's reanalysis of doping tests, which they expect to begin in mid-January.
"The process is ongoing and FIFA will contact Dr Rodchenkov via the agreed channel when the time is right," world football's governing body said.
Rodchenkov is the former director of the Moscow anti-doping laboratory. He fled to the United States in 2016 saying he feared for his life after the sudden death of two senior officials in the Russian Anti-Doping Agency (RUSADA).
He then provided information which led to an investigation of doping at the Sochi Winter Games in 2014.
Since then, Russian athletes have been banned from the Rio Olympics in 2016 and Russia has been barred from participating at February's Winter Olympics in Pyeongchang, South Korea, though athletes who are deemed "clean" can compete under the Olympic flag.
The spotlight has turned to possible cases of doping in football with Russia set to host the World Cup in June and July.
However, FIFA president Gianni Infantino insisted earlier this month that all tests carried out thus far had come back negative.
"If you would have a serious doping issue in football this would be known by now, whether in Russia or any other country of the world," Infantino said in Moscow prior to the draw for the World Cup on December 1.