Adviser to the Head of the Ukrainian President s Office Mykhailo Podoliak. Photo courtesy of President of Ukraine Volodymyr Zelenskyy official website.
"Ukraine is watching the events in the Belgorod region of Russia with interest and is studying the situation, but has nothing to do with it," Ukrainian presidential advisor Mikhaylo Podolyak said.
Ukraine has previously denied responsibility for several reported sabotage attacks on Russian territory.
Russia said earlier that a group of saboteurs had crossed from Ukraine into Belgorod region and Russian troops and agents were trying to "eliminate" them.
Podolyak suggested that Russian "guerrilla groups" could be responsible.
"The only driving political force in a totalitarian country of tightened screws is always an armed guerrilla movement," he said.
"As you know, tanks are sold at any Russian military store, and underground guerrilla groups are composed of Russian citizens."
Russia has said the incursion was designed by Ukraine to "divert attention from Bakhmut", after Moscow claimed to have captured the city over the weekend, but Kyiv denied this.
The reported incursion came ahead of a widely expected counteroffensive by Kyiv.