The Kremlin insisted Tuesday that Russia has made its last debt restructuring offer to Ukraine as the clock ticks down on a deadline that could see Kiev pushed into default.

"Russia put forward an offer for restructuring ... Unfortunately our interlocutors have not accepted this initiative," Kremlin spokesperson Dmitry Peskov said.

Moscow and Kiev are locked in a dispute over $3 billion Russia loaned former president Viktor Yanukovych in 2013.

 Russian President Vladimir Putin said last month that Moscow was ready to spread out the repayment over three years after initially demanding that Kiev make good on the full amount by late December.