"The short-sighted steps by the United States that resulted in the killing of Qasem Soleimani lead to a sharp escalation of the military-political situation in the Middle East region and to serious negative consequences for the entire global security system", the ministry said in a statement.
The ministry said that long before the US-led coalition, Soleimani had organised armed resistance to the Daesh* terrorist group and al-Qaeda* in Syria and Iraq.
"His personal merits in fighting against Daesh on Syrian territory are unquestionable", it said.
The statement comes after Soleimani and Iraqi militia commander Abu Mahdi al-Muhandis along with 10 other people were killed on Friday morning in an airstrike on the outskirts of Baghdad that was authorized by US President Donald Trump.
In Iran, Supreme Leader Ali Khamenei and President Hassan Rouhani vowed to avenge Soleimani’s assassination.
*Daesh (also known as ISIS/ISIL/IS) and Al Qaeda are terrorist groups banned in Russia