MOSCOW, Russia -- Russian President Vladimir Putin told the visiting UN chief Tuesday that he still had hope for negotiations to end the conflict in Ukraine.

"Despite the fact that the military operation is ongoing, we still hope that we will be able to reach agreements on the diplomatic track," Putin told UN Secretary-General Antonio Guterres, who was visiting Moscow, in televised remarks.

"We are negotiating, we do not reject (talks)." Sitting across from Guterres at a long table at the Kremlin, Putin said efforts at talks with Ukraine had been derailed by claims of atrocities committed by Russian forces in the town of Bucha outside Kyiv.

"There was a provocation in the village of Bucha, which the Russian army had nothing to do with," Putin said. "We know who prepared this provocation, by what means, and what kind of people worked on it." Ukraine had proposed an international agreement whereby other countries would guarantee its security. In return, Kyiv would not join NATO or host foreign military bases and become a neutral, non-nuclear state.

The talks in Turkey stalled after the discovery of civilian bodies in areas near Kyiv previously occupied by Russian forces.

Putin told Guterres he was "aware of your concerns about Russia's military operation" in Ukraine and ready to discuss it, but blamed the turmoil in the country on an "anti-state coup" that overturned a pro-Russian president in 2014.

Guterres reiterated his call from an earlier meeting with Foreign Minister Sergei Lavrov for Moscow and Kyiv to work together with the UN to set up aid and evacuation corridors to help civilians in Ukraine.

The UN chief's spokesman Stephane Dujarric said Putin agreed "in principle" to the United Nations and the International Committee of the Red Cross being involved in evacuating civilians from the Azovstal steelworks in the port city of Mariupol.

Further discussions will take place between the UN Office for the Coordination of Humanitarian Affairs and the Russian defence ministry, he added.