More than 1,000 Russian soldiers have died during the military operation in Ukraine, Moscow announced Friday, adding that 93% of the territory of Luhansk province has been "liberated" by the self-proclaimed Luhansk People's Republic (LNR), while Donetsk People's Republic (DNR) has taken control over 54% in Donetsk province.

Russian news agencies quoted the defense ministry as saying that some 1,351 soldiers have been killed since the end of February,

"Unfortunately, during the special military operation there are losses among our comrades. To date, 1,351 servicemen have died and 3,825 have been injured," it said in a statement. The ministry earlier said that the main targets of the first phase of Russia's "special operation" in Ukraine had been completed.

However, according to Ukraine's information, they claim around 15,600 Russian troops were killed in just one month of fighting – almost 15 times the number that Russia declared Friday.

The ministry asserted that there are many requests from Russians who want to take part in the operation in Ukraine. More than 23,000 foreigners from 37 countries expressed their readiness to fight on the side of the eastern republics.

"We offered the leadership of the LNR and DNR to accept this assistance, but they said that they would defend their land themselves," the ministry said.

The ministry said Russia would continue with its operation until it achieved the targets set by President Vladimir Putin, RIA reported.

The ministry added that it did not rule out storming Ukrainian cities that had been blockaded and that Russia would react immediately to any attempt to close the airspace over Ukraine – something Kyiv has asked NATO to do, but NATO has resisted.

Russia sent tens of thousands of troops into Ukraine on Feb. 24 in its "special operation" to weaken its southern neighbor's military capabilities and root out people it called "dangerous nationalists."

Ukrainian forces have mounted stiff resistance to the invasion and the West has imposed sweeping sanctions on Russia in an effort to force it to withdraw its forces.

Russia's military had considered two options for its operation in Ukraine, one confined to the Donbass and the other on the whole territory of Ukraine, the defense ministry said.