The Russian Defense Ministry Thursday announced the start of military exercises with the participation of more than 10,000 soldiers near the border with Ukraine.
The exercises are held at different training sites in the south of the country, including near cities of Volgograd, Astrakhan, Stavropol, Rostov, and Krasnodar, the ministry said in a statement.
The military personnel will train in tactical actions as part of reconnaissance and offensive operations, the statement added.
On Wednesday, Russia and NATO held a meeting in Brussels regarding security issues, including the situation in Ukraine.
After the meeting, Russian Deputy Foreign Minister Aleksandr Grushko said Moscow expects a "definite" response from NATO to Russia's proposals on security guarantees.
Russia, Ukraine, and NATO have stepped up military exercises as tensions have intensified in recent weeks as Kyiv has openly accused Moscow of planning to stage an invasion.
Russian forces entered the Crimean Peninsula in February 2014, with President Vladimir Putin formally dividing the region into two separate federal subjects of the Russian Federation the following month.
Turkey and the US, as well as the UN General Assembly, view the annexation as illegal.
According to the UN, fighting between the Ukrainian government forces and pro-Russian separatists in Donbas has seen more than 13,000 people killed since 2014.
The region is one of several sources of friction between Russia and Ukraine.