This is allegedly to prevent Kurdish militants from solidifying positions close to the Turkey – Syria border.
The remarks were made by Russian Foreign Minister Sergei Lavrov on Russian television news, Associated Press reported.
“Turkey has started to declare it has a sovereign right to create some safety zones on Syrian territory,” Lavrov said in the TV interview.
“According to our information, they are digging in a few hundred meters from the border inside Syria.”
He added: “It’s a sort of creeping expansion.”
The comments are the latest development in a tense relationship between Turkey and Russia.
In November 2015, Turkey shot down a Russian Su-24 military aircraft which it says violated its airspace.