The Ukrainian military hardware remaining in Crimea is in operational condition and the decision on Russian President Vladimir Putin's offer to return it will be made by the Ukrainian leadership, Ihor Voronchenko, commander of the Ukrainian Navy, said.

"The decision will be made at the level of the top military and political administration of the state. But this issue needs to be thoroughly studied," he said on 112.Ukraine TV channel on Thursday.

Voronchenko said there were eight combat ships in Crimea and only one of them, the big landing ship Olshansky, was not in running condition, and the corvette Lutsk was undergoing maintenance.

There are enough infantry fighting vehicles to equip two battalions and also enough armored personnel carriers for two battalions in the coastal units, Voronchenko said. There were seven artillery divisions and four mortar batteries, he said.

The aircraft have been flown to 'mainland Ukraine', he also said.

Voronchenko said official Kyiv had gone to international courts regarding the hardware and the ships that remained in Crimea.

Russian President Vladimir Putin said on Thursday Russia is ready to give Ukraine its combat equipment left in Crimea.