KYIV — Ukraine yesterday accused Russia of deliberately targeting civilians after 30 people were killed when two buses were blown up in the frontline city of Kramatorsk, in one of the deadliest attacks in weeks

President Volodymyr Zelensky vowed that the attack “will not go unanswered” after photos posted by local authorities showed the burnt-out metal shell of the vehicles, with bodies and debris strewn across the road.

“Russia is trying to destroy all life in (the) Donbas (region) and the world must respond to this,” Zelensky wrote on Telegram, warning the death toll could rise.

US Secretary of State Marco Rubio warned that the current stalemate after nearly five years of fighting was “very dangerous” and could lead to escalation.

Zelensky confirmed that Ukrainian negotiators were headed to the United States for talks today and tomorrow with a US team.

“We are also counting on a European team to join our negotiating group,” he added.

US sources told AFP that officials from Britain, France, Germany, NATO and the European Union were invited to the talks.

“They will discuss new ideas and proposals that American negotiators began developing with the Russians and Ukrainians during their recent visit to the region”, one of the US sources familiar with the talks told AFP.

“They are all nervous about the winter. It will be a tough winter if the war does not stop,” the US source said.