Moscow on Wednesday denied allegations that it was beefing up military presence near the Ukrainian border.

"Russia repeatedly said it did not undertake any substantial unusual or non-scheduled military activity near Ukraine's borders, " the Russian Foreign Ministry said in a statement, adding several international inspections held in March had verified that.

On the contrary, it said, Russia has noticed statements from the United States and NATO regarding the alliance's decision to deploy troops in eastern Europe, the Baltic and Black Sea regions.

"Questions were addressed directly to NATO," the ministry said.

On Monday, Russia refused to participate in a meeting of the Organization for Security and Cooperation in Europe (OSCE), which was initiated by Washington and Kiev over their concerns about alleged Russian military activities in regions bordering Ukraine.

Meanwhile, the ministry urged Washington and other states to "stop using the OSCE for pumping tension over Ukraine."

US Secretary of State John Kerry on Tuesday accused Russian agents of stirring unrest in eastern Ukraine that could be used as a pretext for military intervention.