Kiev has been battling a pro-Moscow insurgency in two breakaway eastern regions bordering Russia since 2014, shortly after the Kremlin annexed Ukraine's Crimean peninsula.

Western countries accuse Russia of plotting to invade Ukraine and massing around 100,000 troops on the ex-Soviet country's borders.

Late Wednesday the Organisation for Security and Cooperation in Europe said that Russia and Ukraine had agreed to restore a ceasefire in eastern Ukraine.

On Thursday however, Kiev and separatists accused each other of new violations, and a separatist representative denied that a new truce had been negotiated.

"There is no agreement," Rodion Miroshnik, a representative of the self-proclaimed Lugansk People's Republic, said on messaging app Telegram.

"But if you really want to make a statement about one, why not make it?"

Donetsk authorities also claimed a civilian was injured early Thursday on the outskirts of their de facto capital Donetsk in an attack by Kiev's forces.

The Ukrainian army for its part reported that the separatists launched three attacks on its positions on Thursday.

The army said in a statement that the separatists used large-calibre mortars and grenade launchers but reported no casualties.

All previous ceasefire agreements -- including the previous truce agreed in July 2020 -- crumbled.

- 'Respect the ceasefire' -

Late Wednesday the representative of the OSCE chairperson-in-office in Ukraine, Mikko Kinnunen, said in a statement: "I was delighted that participants expressed their strong determination to fully adhere to the measures to strengthen the ceasefire agreement of July 22, 2020."

The statement was issued following a meeting of officials from Ukraine, Russia and the OSCE -- known as the Trilateral Contact Group -- and representatives of the separatist statelets.

Germany and France welcomed the announcement.

"We urge the sides to respect the ceasefire and to continue discussions on further steps in the humanitarian field," spokespersons of the countries' foreign ministries said in a joint statement.

Ukraine expressed cautious optimism following the agreement.

"There is a sense of a real possibility for the first time in a long while to ensure a ceasefire on the contact line," Andriy Kostin, a Ukrainian representative, said in a statement earlier Thursday.

Russian foreign ministry spokeswoman Maria Zakharova said that the separatists had always respected the 2020 truce and accused Kiev of violations.

"We expect Kiev to observe all of its commitments to ensure a sustainable ceasefire in eastern Ukraine," she said.

The fighting has claimed more than 13,000 lives since 2014.

Ukraine and its Western allies accuse Russia of sending troops and arms across the borders. Moscow has denied those claims.