By Emma Farge
GENEVA (Reuters) -The mayor of Kyiv urged European politicians to cut all commercial ties with Moscow, saying on Tuesday that all payments to Russia were "bloody money" that would fuel what he called a "genocide of Ukrainians".
The United States and Europe are planning new sanctions after dead civilians were found in recaptured satellite towns near Kyiv, including a shallow mass grave in Bucha, but Russian gas exports to Europe continue.
Moscow has dismissed the reports of civilian killings in Bucha as "fakes" aimed at discrediting Russia.
"Every Euro, every cent that you receive from Russia or that you send to Russia has blood, it is bloody money and the blood of this money is Ukrainian blood, the blood of Ukrainian people," Vitali Klitschko, dressed in military clothes, told a mayors' conference in Geneva via video link.
"You can't be half-pregnant. Right now the war is black and white. Are you for peace and support Ukraine or do you support the aggressors, Russia?," he added in a message to politicians.
Klitschko described seeing the bodies of civilians, including an old woman, during visits to Bucha and other towns near Kyiv in the past two days. A car with a white flag and the letters "children" on the outside had been shot up and had blood inside, he said, adding that officials were looking for the occupants' bodies.
Russia has denied any accusations related to the murder of civilians and said it would present "empirical evidence" to a meeting of the United Nations Security Council on Tuesday proving its forces were not involved.
Klitschko, a former heavyweight boxer, said life in the capital was improving, with some people returning, but described the situation in eastern Ukraine as "critical". His counterpart in besieged Mariupol had told him that 5,000 civilians had so far died there, without giving details.
Klitschko repeated a call for more defensive weapons for Ukraine, saying it was in Europe's own interests to do so.
"This war can touch everyone in European countries. Where is the end of Russia's ambitions?," he said.
(Reporting by Emma FargeEditing by Madeline Chambers and Catherine Evans)