Russia's Foreign Minister Sergei Lavrov says it is not 100 percent clear that Russian embassy workers taken hostage in Iraq have been killed.
Lavrov told Russian television Monday that experts are studying an Internet video that purportedly shows the killing of three of the four hostages. He said the video posted Sunday was old and dated from mid-June.
An al-Qaida-linked insurgent group (the Mujahedeen Shura Council) said it killed the four Russians to avenge the alleged torture and killing of its "brothers and sisters" by Russia's government.
The four were abducted earlier this month in an attack that killed a fifth Russian.
Earlier, Iraqi Prime Minister Nouri al-Maliki unveiled a reconciliation plan intended to reduce violence by insurgents and sectarian groups.
Mr. Maliki told parliament the plan includes an offer of amnesty to those who have not taken part in criminal and terrorist activities.
The White House welcomed the national reconciliation plan, saying the process will take time to develop.
But some U.S. lawmakers say they would condemn any plan that gives amnesty to those responsible for killing U.S. soldiers in Iraq.