Sergei Shoigu made the comment during talks with a Swedish military delegation led by Defense Minister Karin Enstrom, RIA Novosti reported.
"It is more of a fight against forces that, one way or another, are roving between different kinds of conflicts within various states," Shoigu said.
The United Nations said at least 93,000 people have been killed since the Syrian conflict broke out in March 2011 between President Bashar Assad's regime and rebels.
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