Western countries are becoming a party to the Ukraine war by sending weapons to Kiev with the aim of prolonging the war by as much as possible, Russian Foreign Minister Sergey Lavrov said Thursday.

"The position of the countries, which are pumping up Ukraine with weapons and military equipment and training military forces of this country, is especially cynical," the Russian foreign minister underlined at the United Nations Security Council meeting.

"The goal is obvious, and they do not hide it, declaring to prolong the fighting as much as possible, despite casualties and damage, so as to pull apart and weaken Russia," Lavrov added.

The top Russian diplomat also highlighted that the West's policy meant that its involvement in the conflict made them a party to the war.

Lavrov also used his position to call for holding all parties responsible for the shelling of civilians in the war accountable regardless of their allegiance.

"Criminal cases are being investigated against citizens of the United Kingdom, Canada, the United States, and the Netherlands on the fact of mercenarism and criminal acts in Ukraine. I assure you that all those responsible, regardless of their citizenship, will be held accountable," the minister underlined.

Reveal names of Bucha casualties

The Russian foreign minister revisited what happened in Bucha, where Kiev and Ukraine claimed that the Russian forces committed a massacre against civilians, calling on Western countries and UN chief Antonio Guterres to publish the names of the people shown in videos and photos as killed in Bucha.

Ukraine had published in April footage it claimed shows evidence of crimes committed by the Russian armed forces in Bucha. "All photos and video materials published by the Kiev regime allegedly testifying to some ‘crimes’ committed by Russian soldiers in the town of Bucha, Kiev region, is another provocation," Moscow's Defense Ministry said, adding that all Russian soldiers had withdrawn from the town as early as March 30.

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Kremlin Spokesperson Dmitry Peskov said the photo and video materials disseminated by Ukraine depicting dead civilians on the streets of the Ukrainian town of Bucha northwest of Kiev could be trusted.

"I appeal once again in the presence of the Secretary General and respected ministers: please get the Ukrainian authorities to take an elementary step — publish the names of those people whose corpses were shown in the city of Bucha," Lavrov said at the UNSC meeting.

"I have been asking for this for more than one month. No one hears. No one wants to react. Dear Mr. Secretary General, at least you use your authority, please. I think it will be useful for everyone to deal with this episode," the Russian diplomat added.