"We believe that the circumstances of the incident require study and reflection," Ryabkov told reporters Monday.
He said the incident would be addressed at Tuesday's meeting in Moscow between Russian Foreign Minister Sergey Lavrov and OSCE Secretary General Lamberto Zannier.
Ryablov added that Russia was working on US Secretary of State Rex Tillerson's request to influence the eastern Ukrainian regions.
In Sunday's statement on an OSCE SMM member's death in eastern Ukraine, Tillerson called on Moscow to "use its influence" to carry out a "full, transparent, and timely investigation."
"We reacted quickly to the US request to transfer the body, although I want to emphasize that this issue was decided by the relevant authorities and structures in Luhansk," Ryabkov said when asked to comment on the statement.
Ryabkov added that Foreign Minister Sergey Lavrov had sent his condolences to Tillerson soon after the incident in Pryshyb, Luhansk region where a US paramedic was killed and two OSCE SMM patrol members were wounded.
