The Russian president visited Mongolia in September. But despite the country being formally obligated to arrest the Russian president, he was able to leave Mongolia after his state visit.
Now, the International Criminal Court (ICC) will investigate Mongolia.
"States and those who have accepted the court's decision are bound to arrest and surrender individuals who are subject to an international arrest warrant, regardless of their official title or nationality", writes ICC in a statement.
ICC will therefore, "considering the seriousness of Mongolia's failure to cooperate with the court", refer the matter to its oversight committee, which meets in December.
Already when Putin's visit was announced, it was criticized, and warnings came that Mongolia is likely to be prosecuted by ICC for its failure. A prosecution of that kind rarely leads to any serious consequences.
ICC's arrest warrant was issued in March last year and was motivated by the forced transfer of children from Russian-occupied areas in Ukraine.
The Mongolia visit was the first time since the order was issued that Putin traveled to a state that has ratified the Rome Statute.