China does not seek selfish geopolitical gains or to do anything that adds fuel to the fire over the Ukraine crisis, and peace is the only goal that the nation has been hoping for, State Councilor and Foreign Minister Wang Yi told his Ukrainian counterpart Dmytro Kuleba on Monday.

In a phone conversation with Kuleba, Wang reiterated Beijing's position encouraging peace talks over the Ukraine issue, saying that it has long been China's historical and cultural tradition and its consistent foreign policy to uphold peace and oppose war.

China welcomes peace talks between Russia and Ukraine, and the two sides should adhere to the general direction of talks in spite of all difficulties or conflicts, until they lead to a cease-fire and peace, he said.

China believes that the Ukrainian side has sufficient wisdom to make choices that fit in with the fundamental interests of its people, he said, adding that China will continue to play a constructive role from an objective and just position.

Kuleba said Ukraine attaches importance to China's global influence and prestige, and the nation hopes that Beijing can continue to play an important role in a cease-fire.

He expressed gratitude for China's humanitarian assistance, saying that Ukraine is still committed to peace talks with Russia to find a lasting solution.

In another development, Moscow has requested a special UN Security Council meeting on Monday to address claims that Russian forces had committed "atrocities against Ukrainian civilians" in Bucha, a town outside Kyiv.

Dmitry Polyansky, Russia's deputy ambassador to the United Nations, said Russia requested a meeting "in the light of heinous provocation of Ukrainian radicals".

Local authorities in Bucha said they had been forced to dig communal graves to bury the dead accumulating in the streets, including some found with their hands bound behind their backs in scenes that sent shock waves through international capitals more than a month into Russia's "special military operation".

Ukraine's President Volodymyr Zelensky was unsparing in his nightly video message, saying that "concentrated evil has come to our land".

Bucha Mayor Anatoly Fedoruk said 280 bodies were placed in mass graves because it was impossible to bury them, as cemeteries lay within range of ongoing shooting.

Satellite imagery company Maxar released photos it said showed a mass grave on the grounds of a church in the town.

On Monday, Russia's Tass News Agency quoted Russian Ambassador to the United States Anatoly Antonov as saying: "I would like to point out that Russian troops left Bucha on March 30. The Ukrainian authorities remained silent all these days, and now they have suddenly posted sensational footage in order to tarnish Russia's image and make Russia defend itself."

On Sunday, Russia's Defense Ministry denied Ukraine's accusations that Russian troops had killed civilians in Bucha, describing the video footage and photographs of dead bodies as a "provocation" and a "staged performance" by Kyiv for the Western media.

The ministry said that all Russian military units had left Bucha last Wednesday, and that civilians had been free to move around the town or evacuate while it was under Russian control.

Ukraine's Foreign Minister Dmytro Kuleba accused Russia on Sunday of a "deliberate massacre," while Zelensky's spokesman, Sergey Nikiforov, said the killings in Bucha look "exactly like war crimes."

The Russian Defense Ministry pushed back, saying "not a single local resident" in Bucha suffered violence during the time that Russian armed forces were in control of the settlement.

The United Nations Secretary-General Antonio Guterres tweeted on Monday that he was "deeply shocked" by images of dead civilians in Bucha, and he called for an independent investigation that "leads to effective accountability".

Separately, China denied a report by London-based The Times citing the Ukrainian security service about its involvement in "a cyberattack on Ukraine before Russian military action".

A spokesperson for Chinese embassy to the United Kingdom called the report "sheer irresponsible talk" and lacking in credibility.

The spokesperson said that for some time The Times' reports on China have been untrue, deliberately distorted and even slanderous and that this "seriously runs counter to the professional ethics of journalism and misleads the readers".